Using the python electrum wallet sources, Komodo developer pbca26 was able to demonstrate to discord user zrtx goal on how to sign a raw transaction. The conversation included zCash protocol expert dukeleto, atomicDEX API & marketmaker developer artem.pikulin.
Electrum wallet is fully capable of signing correct kmd/kmd smartchain transactions and worked so far w/o any major issues. 99% of it's core code is inherited from zcash electrum wallet version. Here is the resulting gist (embedded below edit: the gist has been removed) from pbca26 to achieve the goal below:
komodo-cli createrawtransaction -> unsigned tx hash -> transaction lib of electrum-komodo -> signed tx hash