Sorry for delay in reply:
What was the game engine version - standard or experimental - and pak set/version used to generate the SR 1750 v2 file?
current latest Simutrans standard v102.2.1 - the clue is in the savefile name

current latest Pak-GB (v1.6)
Its 8 Meg sizes is very interesting ...
I notice that the other conversation has since developed somewhat, but re this map; I deliberately made it start off 'bald', adding only minimal trees, on advice given by Prissi and Dwachs
here.
- Glad you like it, as a test piece it seems to be serving a useful function!
personally, I can't run that sort of map size and like to keep the sizes below 1.2gb, or basically a size that fits within the half my computer's memory.
How are you calculating the 1.2Gb? Just by observation of realtime memory usage? I mean, is there a way of working backwards from an amount of RAM available, to give a 'maximum reasonable' map size? Or is it just a trial an error thing? Because it appears RAM usage and savefile size do not necessarily correlate. And whilst big maps are interesting, playable maps are more useful!