Interesting! Yes, I see how Z could trip up Polish with the AngleZ mod. One possibility is using FatZ with the Z on the former LShift key, but tweaking modifiers can be a bit tricky unless you're on a programmable keyboard in which case it's simple enough.
[Edit: OK, I've uploaded the Wiechciu Cmk-eD-Pl_ANS_CurlAWide variant with the latest EPKL commit just now. It's got the marked ZXCV positions for the Extend shortcuts, using a custom Extend remap and local Extend help images. I didn't fix the Extend3 Kaomoji layer, but these days I use the MoDK Shift+Ext-tap Kaomoji dead key instead of Ext3 anyway. I did not upload the dead key images you generated, so users have to make their own if they use that layout. Note that to use them you need to have img_DKeyDir = .\DeadkeyImg in the layout.ini file.]