If you havent tried already, space platform would be freezing your game everytime a tile of the platform is build or deleted.
Reason behind it is that Astreroid Collector (Transcendent x240) have Collection area: 60295x60295 and game have to recalculate that everytime a tile is placed. Even if you have no Asteroid Collectors build on the platform.

Here is the link to bug report if that is interesting:
https://forums.factorio.com/viewtopic.php?p=661819#p661819
Even if you created the platform with Additional Qualities and it was set to high, disabling the mod would not fix it, you have to delete and remake space platform.

At this point i would think a fix would be limiting Asteroid Collectors from scaling THAT high.
There is a possibility that more broken things exist, but so far this is game breaking.

https://i.imgur.com/PMWH72J.png