It is possible to make a swapdisc of a real ps2 demo disc, but ....
U must find someone who has a REALLY old Action Replay (AR) or Game Shark (GS) and borrow the files from them and u need the toc-list..
In order to boot AR or GS u will need to have a real AR or GS Dongle (cheatcartrige).
The demo cd/dvds dosnt ever spin down (none ive tried spins down, not even at the "keys"-screen).. so when u have to swap u have to swap runnin'.
So its possible ... but its way more easy to just buy a real swapmagic-disc set.
PSP 1.52 (DG), DS 001, XBOX v1.6B+Cheapmod+120GBHD, SM33, 50004+HDA10+120GBHD, SM32, BP11, 3900X, XBOX v1.6+Softmod, P4_2.666, GBASP, GBA,Celeron_700, DC, PS1, P2_300, TI85, Saturn, GBC, GBP, Megadrive, P75, Amiga 500, MS, 486SX25, Amstrad CPC464, ZX81