They were all build in the same environment, so I expect same results, don't put too much effort in this.
The question for me was if something happened to that environment.
But as rc1 worked so far, I assume issues with Big Sur or M1-Chip.
I'm curious about the hardware of recumberic, maybe this brings new insights.
I can't prove this, but my assumption is not the app, but some libraries may be missing or different on Big Sur.
So the app itself wouldn't solve this issue.
If you want to give it a try, there is a build-osx.sh script in the scripts folder.
When you open a terminal and change to the LibreCAD/scrips folder, you can run this script with ./build-osx.sh.
If everything runs well, this should result in a LibreCAD.dmg file in the LibreCAD root folder.
This package should contain everything needed to deploy it on Big Sur.
When this succeeds you can get in touch how to send it to me and I can publish it on the download sites then.
I have tried various different sources and versions but Mac's BigSpur operating system will not allow LibreCAD to be installed. Mac OS wants to immediately put the installer and the DMG into the trash. Until Apple recognises LibreCAD as a legitimate software you will not be able to use it if you have installed BigSpur.