Error in ES module resolution

[zero1zero]

Getting the following error trying to use ES module in the "transform" field:

evalmachine.<anonymous>:385
                        throw new tsp.TsPatchError(`tsconfig.json > plugins: "${configTransformValue}" does not have an export "${importKey}": ` +
                        ^
TsPatchError: tsconfig.json > plugins: "test" does not have an export "default": {}
    at TspPlugin.createFactory (evalmachine.<anonymous>:385:31)
    at PluginCreator.createProgramTransformers (evalmachine.<anonymous>:294:56)
    at Object.createProgram (evalmachine.<anonymous>:582:55)
    at createProgram (evalmachine.<anonymous>:125324:41)
    at getBuilderCreationParameters (evalmachine.<anonymous>:129626:18)
    at createEmitAndSemanticDiagnosticsBuilderProgram (evalmachine.<anonymous>:130294:5)
    at createIncrementalProgram (evalmachine.<anonymous>:132016:10)
    at performIncrementalCompilation (evalmachine.<anonymous>:131970:30)
    at performIncrementalCompilation2 (evalmachine.<anonymous>:135212:22)
    at executeCommandLineWorker (evalmachine.<anonymous>:134986:7) {
  diagnostic: undefined
}

This was previously mentioned here: #58 (comment), with example failing code here: https://github.com/colecrouter/ts-patch-repro

Is this caused by user error or an ongoing defect? Unclear if this was ever resolved or what the cause of the error is.

Thanks!

[zero1zero]

Worth noting that switching to commonjs for my plugin resolved this particular issue.