I read something about I'm supposed to use protected mode, but I have no idea how, and the README file does not tell me anything except that I need a fast computer..

I have:

Some Intel P4 Motherboard
P4 2.8 GHz Processor
1024 MB of RAM (not sure what type)
ATI Radeon 9700 with 128 MB RAM
Sound Card is Integrated with the Intel Motherboard
Windows XP Pro

I am using the floppy version of Judgment Rites and I tried increasing memory size in Dosbox but that did not work, and I cannot see what error I get because it flashes once then disappears, I think it has something to do with not enough memory. This is using both version 0.63 and 0.65, same results on both, a black screen and nothing happens.