Check the "known problems" link on the left at http://www.ultimatebootcd.com
. You should do it in any case.
After replacing the files from the original ubcd502 (or whatever version you have) with those from "known problems", you should go to the "tutorials" page (not the one at the wiki, but the one on the left at http://www.ultimatebootcd.com
) . There you should find the tutorial about ubcd2iso.
No offense, but just reading simple instructions (like tutorials and FAQ's) should be the first choice, and just then
ask in the forum.