ID:2071495
 
It keeps saying Dream Seeker has stopped working in a window.

I searched the sentence and it appears it was the Windows 10 update problem that many people had, though I'm running Windows Vista and I've never had this problem occur before on this computer.

Any help would be appreciated.

Did DS crash or did it hang? There's a crucial difference, because if it's a crash there should be some info in the Windows event viewer. I'd need to see that, plus anything you could tell me about the game you were playing would be helpful.

If it hung, then it could be something like antivirus or security software interfering. Avast has been known to cause trouble for BYOND since version 509, so that's something to look for also--if not Avast specifically, then it could be some other security program.
I reverted to BYOND 508 and now it's loading one game, but the one I want to play is Naruto Final Fight and instead of immediately saying it's stopped working, it now only says it once the window of NFF has opened.

With 509, it says it stopped working as soon as the game loading window appeared.
1) Faulting application byond.exe, version 5.0.508.1287, time stamp 0x55762146, faulting module mshtml.dll, version 7.0.6001.18000, time stamp 0x4791a74c, exception code 0xc0000005, fault offset 0x000d1492, process id 0xf74, application start time 0x01d198f26a8674a8.

2) Faulting application dreamseeker.exe, version 5.0.508.1287, time stamp 0x55762121, faulting module MSVCR120.dll, version 12.0.21005.1, time stamp 0x524f7ce6, exception code 0x40000015, fault offset 0x000a7676, process id 0xcb4, application start time 0x01d198f273dc8038.

3) Faulting application dreamseeker.exe, version 5.0.508.1287, time stamp 0x55762121, faulting module ntdll.dll, version 6.0.6001.18000, time stamp 0x4791a7a6, exception code 0xc0000005, fault offset 0x000681cb, process id 0x6d4, application start time 0x01d198f290baa338.

And this one happened earlier

Faulting application dreamseeker.exe, version 5.0.508.1287, time stamp 0x55762121, faulting module byondcore.dll, version 5.0.508.1287, time stamp 0x55762044, exception code 0xc0000005, fault offset 0x000313b0, process id 0xf98, application start time 0x01d198dc3a365cca.

and this one is from 509

Faulting application dreamseeker.exe, version 5.0.509.1319, time stamp 0x56901bdd, faulting module d3dx9_43.dll!D3DXCreateTexture, version 6.0.6001.18000, time stamp 0x4791a7a6, exception code 0xc0000139, fault offset 0x00009cac, process id 0xc98, application start time 0x01d198d98a0832da.