problem 2: the time/date
Only parts of the site uses or includes the time difference value which can really peeve people off if waiting to bid at the last moment and they find it closed 2 hours ago.
Fix: Several ways to do this,
A/ do not add any time difference to any value being inputted into the databse and only use it for output or B/ the reverse. Phpauction really needs a complete rewrite and to use functions and class functions, the date/time is one of the many things that would be better used by them. (the dates files doesnt cut it)