Thank you for this!
You are playing on a FPGA right? there is something strange with the color configuration you have... They don't correspond to the real palette of the Zx Spectrum... At least with the one I know! :) Could it be some issue with your configuration?
I allow myself to leave you a video in which the player manages to advance a little more... In case you want to see the other 2 areas of the game... and the original colors we used:
If you back to the game anytime... Keep in mind that there is an important puzzle component, most of the time, the warp mechanic, to cross from one end of the room to the other, makes the "solution" for each level much easier than if you do not use this mechanic to solve the problem at all. ;)
Thanks for playing it and for the video! It always brightens the day to see someone playing the game for the first time. And taking the time to share his impressions.
THANK YOU!