While traveling with my Windows XP laptop, I discovered that in some low-memory situations, Windows may limit Java to 256 MB, which all but prohibits zoom, and also prevents some high-memory scenarios, such as Age of Heroes 2, from opening with maps. A couple things should be done:
I suspect that, other than an XP-ified launcher for sidestepping it in that case, the occasional 256 MB wall is not XP-specific, and would also occur - perhaps more often - on a similar Vista/7/8/10 machine. However, I don't have a low-memory one of those on hand to conveniently test with, and probably won't be bothered to swap in my Vista disk to verify that case.
Found that the Graphics Import does indeed load everything in a temporary buffer, and then again to long-term storage, which will approximately double RAM use. Null-settings things as they aren't needed should help with this.
For AoH2, at least 288 MB of RAM is needed to load (fails at 272 MB). But it only uses about 128 MB once it's loaded. For a custom-everything Standard map, 256 MB is required (fails at 240 MB). But again it only uses about 128 MB after being loaded.
This does suggest the required/recommended specs are set correctly, but some buffer would be nice.
Made significant improvements in 1.22 around graphics-import memory usage, reducing requirements by about 100 MB/40%. Don't have the launcher recommendation when out of memory yet, but what's already been added should address the issue in most cases, so marking as resolved.