Hi George,
I had tried to run your notebook on colab, unfortunately i got disconnected before it’s completed. Nevertheless, I tried to copy your build_select_tf_ops_aar.sh on my machine to compile from source (v2.5.0). I have a slightly different android configurations, ndk version 19c, sdk version 30.0.3. I only attempted to build x86_64. Near the end of the compilation, i still get the following errors:
ERROR: /home/cph/Documents/tensorflowRep/tensorflow/tmp/BUILD:19:28: Listing flex ops from savedTokenizerModel.tflite... //tmp:custom_tensorflowlite_flex_flex_delegate_tf_op_headers_list_flex_ops failed (Aborted): bash failed: error executing command /bin/bash -c ... (remaining 1 argument(s) skipped)
2021-08-05 16:40:20.507129: F tensorflow/lite/tools/list_flex_ops.cc:58] Op CaseFoldUTF8 not found: Not found: Op type not registered 'CaseFoldUTF8' in binary running on cph. Make sure the Op and Kernel are registered in the binary running in this process. Note that if you are loading a saved graph which used ops from tf.contrib, accessing (e.g.) `tf.contrib.resampler` should be done before importing the graph, as contrib ops are lazily registered when the module is first accessed.
/bin/bash: line 1: 36001 Aborted                 (core dumped) bazel-out/host/bin/tensorflow/lite/tools/list_flex_ops_main --graphs=tmp/savedTokenizerModel.tflite > "bazel-out/android-x86_64-opt/bin/tmp/custom_tensorflowlite_flex_flex_delegate_tf_op_headers_tf_generated_kernel_header/list_flex_ops"
Target //tmp:tensorflow-lite-select-tf-ops failed to build
Use --verbose_failures to see the command lines of failed build steps.
INFO: Elapsed time: 6.863s, Critical Path: 1.92s
INFO: 5 processes: 3 internal, 2 local.
FAILED: Build did NOT complete successfully

I am starting to wonder if I need to edit the BUILD files to include tensorflow_text dependancies. In another recent post, thisisjoshstone was attempting to compile tf_text ops onto the benchmark tool. There were some mentions on adding @org_tensorflow_text//tensorflow_text:ops_lib as a dependency. However, I am unfamiliar with the inner workings of how bazel compiles TF libraries.
Anyway, I’m providing a gist model definition in colab, as well as the its converted tflite model in the links below.

The gist model in colab .
The gist’s tflite model.

Also, I’m providing my tflite model that I am working on.

Full tflite model 1.