Improve custom tx error and help msg #716

Job	Run time
changelog	17s
changelog	17s
check-packages	5m 8s
check-packages	5m 8s
build-wasm (wasm, build-wasm-scripts, wasm/tx_.wasm wasm/vp_.wasm wasm/checksums.json )	4m 20s
build-wasm (wasm, build-wasm-scripts, wasm/tx_.wasm wasm/vp_.wasm wasm/checksums.json )	4m 20s
build-binaries	9m 51s
build-binaries	9m 51s
build-wasm (wasm-for-tests, build-wasm-tests-scripts, wasm_for_tests/*.wasm)	3m 0s
build-wasm (wasm-for-tests, build-wasm-tests-scripts, wasm_for_tests/*.wasm)	3m 0s
lints	5m 23s
lints	5m 23s
rust-docs	5m 48s
rust-docs	5m 48s
check-benchmarks	2m 40s
check-benchmarks	9m 47s
test-integration	14m 32s
test-integration	14m 32s
test-wasm	7m 0s
test-wasm	7m 0s
test-unit	10m 29s
test-unit	10m 29s
test-e2e (0)	22m 13s
test-e2e (0)	22m 13s
test-e2e (1)	17m 36s
test-e2e (1)	17m 36s
test-e2e (2)	23m 52s
test-e2e (2)	21m 28s
test-e2e (3)	17m 34s
test-e2e (3)	17m 34s
test-e2e (4)	18m 0s
test-e2e (4)	18m 0s
upload-coverage	8s
upload-coverage	8s
	5h 40m 25s

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