I'm writing this since i'm curious if anyone knows about this. I have tried with the version 1.2 to do the fast bomb technique, and the bomb glitch in Chapter 1A, but they seem to be either really hard to get now, or just not working. Would love to get some insight !

They definitely do work, Hinamega's any% run and my 100% run were both done on 1.2. I personally haven't noticed any increase in difficulty, but I have heard from some that it is more difficult on the switch version, not sure if you are using that one.

All of the glitches in the repository are still in the game in 1.2.

If you want any more specific tips for how to do it, or what you might be doing wrong, feel free to join the discord (or ask on it if you are already there). I am sure whoever is online at the time will be happy to help you troubleshoot.