diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index e5864b2f2..511e4f913 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -7,9 +7,9 @@ This file contains a high-level description of this package's evolution. Release
 
 ## 4.9.2 - TBD
 
-
+* Fix 'make distcheck' error in run_interop.sh. See [Github #????](https://github.com/Unidata/netcdf-c/pull/????).
 * Update `nc-config` to remove inclusion from automatically-detected `nf-config` and `ncxx-config` files, as the wrong files could be included in the output.  This is in support of [GitHub #2274](https://github.com/Unidata/netcdf-c/issues/2274).
-* [Bug Fix] Update H5FDhttp.[ch] to work with HDF5 version 1.14.0. See [Github #2615](https://github.com/Unidata/netcdf-c/pull/2615).
+* Update H5FDhttp.[ch] to work with HDF5 version 1.14.0. See [Github #2615](https://github.com/Unidata/netcdf-c/pull/2615).
 
 ## 4.9.1 - February 2, 2023
 
diff --git a/libhdf5/H5FDhttp.h b/libhdf5/H5FDhttp.h
index 6d4553998..2e0e11db8 100644
--- a/libhdf5/H5FDhttp.h
+++ b/libhdf5/H5FDhttp.h
@@ -30,7 +30,7 @@
 #include "H5Ipublic.h"
 
 #if H5_VERSION_GE(1,14,0)
-#define H5_VFD_HTTP     ((H5FD_class_value_t)(H5_VFD_MAX - 2))
+#define H5_VFD_HTTP     ((H5FD_class_value_t)(514))
 #define H5FD_HTTP	(H5FDperform_init(H5FD_http_init))
 #else
 #define H5FD_HTTP	(H5FD_http_init())
diff --git a/nczarr_test/Makefile.am b/nczarr_test/Makefile.am
index 3e04bb7c7..5e1237699 100644
--- a/nczarr_test/Makefile.am
+++ b/nczarr_test/Makefile.am
@@ -164,7 +164,8 @@ ref_string.cdl ref_string_nczarr.baseline ref_string_zarr.baseline ref_scalar.cd
 ref_nulls_nczarr.baseline ref_nulls_zarr.baseline ref_nulls.cdl
 
 # Interoperability files
-EXTRA_DIST += ref_power_901_constants_orig.zip ref_power_901_constants.cdl ref_quotes_orig.zip ref_quotes.cdl 
+EXTRA_DIST += ref_power_901_constants_orig.zip ref_power_901_constants.cdl ref_quotes_orig.zip ref_quotes.cdl \
+ref_zarr_test_data.cdl.gz
 
 CLEANFILES = ut_*.txt ut*.cdl tmp*.nc tmp*.cdl tmp*.txt tmp*.dmp tmp*.zip tmp*.nc tmp*.dump tmp*.tmp tmp_ngc.c ref_zarr_test_data.cdl tst_*.nc.zip ref_quotes.zip ref_power_901_constants.zip
 
diff --git a/nczarr_test/run_interop.sh b/nczarr_test/run_interop.sh
index f3b9ea232..f3d7812d8 100755
--- a/nczarr_test/run_interop.sh
+++ b/nczarr_test/run_interop.sh
@@ -17,35 +17,35 @@ UB="${NCZARR_S3_TEST_BUCKET}"
 
 testcasefile() {
   zext=file
-  ref=$1
+  base=$1
   mode=$2
   metaonly=$3
   if test "x$metaonly" = xmetaonly ; then flags="-h"; fi
-  fileargs ${execdir}/$ref "mode=$mode,$zext"
-  rm -f tmp_${ref}_${zext}.cdl
-  ${NCDUMP} $flags $fileurl > tmp_${ref}_${zext}.cdl
-  diff -b ${srcdir}/${ref}.cdl tmp_${ref}_${zext}.cdl
+  fileargs ${builddir}/ref_$base "mode=$mode,$zext"
+  rm -f tmp_${base}_${zext}.cdl
+  ${NCDUMP} $flags $fileurl > tmp_${base}_${zext}.cdl
+  diff -b ${srcdir}/ref_${base}.cdl tmp_${base}_${zext}.cdl
 }
 
 testcasezip() {
   zext=zip
-  ref=$1
+  base=$1
   mode=$2
-  fileargs $ref "mode=$mode,$zext"
-  rm -f tmp_${ref}_${zext}.cdl
-  ${NCDUMP} -h $flags $fileurl > tmp_${ref}_${zext}.cdl
-  diff -b ${srcdir}/${ref}.cdl tmp_${ref}_${zext}.cdl
+  fileargs ${builddir}/ref_$base "mode=$mode,$zext"
+  rm -f tmp_${base}_${zext}.cdl
+  ${NCDUMP} -h $flags $fileurl > tmp_${base}_${zext}.cdl
+  diff -b ${srcdir}/ref_${base}.cdl tmp_${base}_${zext}.cdl
 }
 
 testcases3() {
   zext=s3
-  zarr=$1
-  ref=$2
-  mode=$3
-  rm -f tmp_${zarr}_${zext}.cdl
-  url="https://${UH}/${UB}/${zarr}#mode=${mode},s3"
-  ${NCDUMP} $url > tmp_${zarr}_${zext}.cdl
-  diff -b ${srcdir}/${ref}.cdl tmp_${zarr}_${zext}.cdl
+  base=$1
+  mode=$2
+  rm -f tmp_${base}_${zext}.cdl
+  url="https://${UH}/${UB}/${base}.zarr#mode=${mode},s3"
+  ${NCDUMP} $url > tmp_${base}_${zext}.cdl
+  # Find the proper ref file
+  diff -b ${builddir}/ref_${base}.cdl tmp_${base}_${zext}.cdl
 }
 
 testallcases() {
@@ -54,27 +54,35 @@ case "$zext" in
     file)
 	# need to unpack
 	rm -fr ref_power_901_constants ref_power_901_constants.file
-	unzip ${srcdir}/ref_power_901_constants_orig.zip > /dev/null
-	mv ref_power_901_constants ref_power_901_constants.file
-	testcasefile ref_power_901_constants zarr metaonly; # test xarray as default
+        if ! test -f ${builddir}/ref_power_901_constants_orig.zip ; then
+          cp -f ${srcdir}/ref_power_901_constants_orig.zip ${builddir}/ref_power_901_constants_orig.zip
+	fi
+	unzip ${builddir}/ref_power_901_constants_orig.zip > /dev/null
+	mv ${builddir}/ref_power_901_constants ${builddir}/ref_power_901_constants.file
+	testcasefile power_901_constants zarr metaonly; # test xarray as default
 	;;
     zip)
 	# Move into position
-        cp ${srcdir}/ref_power_901_constants_orig.zip ${execdir}/ref_power_901_constants.zip
-        cp ${srcdir}/ref_quotes_orig.zip ${execdir}/ref_quotes.zip
-	testcasezip ref_power_901_constants xarray metaonly
+        if ! test -f ${builddir}/ref_power_901_constants.zip ; then
+          cp -f ${srcdir}/ref_power_901_constants_orig.zip ${builddir}/ref_power_901_constants.zip
+        fi
+        if ! test -f ${builddir}/ref_quotes.zip ; then
+          cp -f ${srcdir}/ref_quotes_orig.zip ${builddir}/ref_quotes.zip
+	fi
+	testcasezip power_901_constants xarray metaonly
 	# Test large constant interoperability 
-	testcasezip ref_quotes zarr metaonly
+	testcasezip quotes zarr metaonly
 	;;
     s3)
 	# Read a test case created by netcdf-java zarr.
 	# Move into position
-        rm -f ${execdir}/ref_zarr_test_data.cdl
-	# Use gunzip because it always appears to be available
-	if ! test -f ${srcdir}/ref_zarr_test_data.cdl ; then
-            gunzip -c ${srcdir}/ref_zarr_test_data.cdl.gz > ${srcdir}/ref_zarr_test_data.cdl
+        rm -f ${builddir}/ref_zarr_test_data.cdl
+        if ! test -f ${builddir}/ref_zarr_test_data.cdl.gz ; then
+	  cp -f ${srcdir}/ref_zarr_test_data.cdl.gz ${builddir}/ref_zarr_test_data.cdl.gz 
 	fi
-        testcases3 zarr_test_data.zarr ref_zarr_test_data xarray
+	# Use gunzip because it always appears to be available
+        gunzip -c ${builddir}/ref_zarr_test_data.cdl.gz > ${builddir}/ref_zarr_test_data.cdl
+        testcases3 zarr_test_data xarray
  	;;
     *) echo "unimplemented kind: $1" ; exit 1;;
 esac
@@ -83,9 +91,9 @@ esac
 testallcases file
 if test "x$FEATURE_NCZARR_ZIP" = xyes ; then testallcases zip; fi
 if test "x$FEATURE_S3TESTS" = xyes ; then testallcases s3; fi
-exit
+
 # Cleanup
-rm -fr ${execdir}/ref_power_901_constants.file
-rm -f ${execdir}/ref_zarr_test_data.cdl
+rm -fr ${builddir}/ref_power_901_constants_orig.zip
+rm -fr ${builddir}/ref_zarr_test_data.cdl.gz
 
 exit 0
diff --git a/nczarr_test/s3util.c b/nczarr_test/s3util.c
index 07e03ef1c..0852a45a0 100644
--- a/nczarr_test/s3util.c
+++ b/nczarr_test/s3util.c
@@ -128,7 +128,7 @@ main(int argc, char** argv)
 
     dumpoptions.nctype = NC_UBYTE; /* default */
 
-    while ((c = getopt(argc, argv, "df:k:p:t:T:u:v")) != EOF) {
+    while ((c = getopt(argc, argv, "df:hk:p:t:T:u:v")) != EOF) {
 	switch(c) {
 	case 'd': 
 	    dumpoptions.debug = 1;	    
@@ -136,6 +136,9 @@ main(int argc, char** argv)
 	case 'f':
 	    dumpoptions.filename = strdup(optarg);
 	    break;
+	case 'h':
+	    usage();
+	    return 0;
 	case 'k': {
 	    size_t len = strlen(optarg);
 	    dumpoptions.key = (char*)malloc(len+1+1);