Sounds like you have not loaded a Zeropain module, right there are two ways to beat the problem,
download a fixed Zero page module http://www.heyrick.co.uk/random/zeropain_noexpire.zip
Open !Boot by holding shift key and double clicking with select navigate to PreDesk folder inside (!Boot/Choices.Boot.PreDesk)
copy the unpacked module here (check to see if there is a folder !!ZeroPain already there if there is put it side overwrite the current module , then reboot to check if the software that you wanted to use works now.
Second way to skin the cat is to install a low vector build of Risc OS that don't need the zeropain module.
download low vector build here http://www.svrsig.org/software/Update4.zip
to your (Mac OR PC) Then repeat step Six from lesson two (you will notice that the filename is the same as last time, but when you open it it don't have the choices folder this is because Chris the guy that went to all the trouble to package these updates renamed the the high vector build to update3.zip if you need this build here is the new download link http://www.svrsig.org/software/Update3.zip
any problems post here but also check out this post https://www.riscosopen.org/forum/forums ... osts-51543
feel free to ask questions there is always someone willing to help.