Specifically, it says:
"Script error, "paranoic.pk3: decorate/weaponsammo.txt" line 385:
Unexpected 'misc/w_pkup' in definition of 'PShellBox'"
There are also script errors on line 380 & 385, ("Parent type 'PShell' not found in PShellBox" and "'inventory.pickupsound' requires an actor of type 'inventory'")
I suspect that these are just the start of other errors, but the error checking got interrupted when execution could not continue.
I am able to use G2.2pre-342-gd90f2ba just fine. So something between these 2 versions (Feb 6 & Feb

System specs are:
Processor: Intel Core 2 4400 @ 2 GHz
RAM: 2 GB
OS: Windows 7 Home Premium, 32-bit
DirectX: 11.0
Graphics Card: NVIDIA GeForce GT 240
Dedicated video memory: 1024 MB GDDR5