does the custom template that you customized yourself not have any documentation as to what you changed? i suppose you could do this, if it were only CSS that you modded, you can run DIFF on the CSS files from 7.0.3 against your CSS files, this will give you some inkling as to what was changed by you to customize your template.
now ok you have that locked down
now looking at the 7.0.3 DIFF 7.0.4 CSS
and DIFF 7.0.3/modules/boonex/forum/layout --> 7.0.4 /modules/boonex/forum/layout
if you do not know what files you edited, there is not much hope in any of us knowing what you edited. SVN baby, develop in SVN
alternatively and as the last resort so at least you are making progress, load UNI template on 7.0.4 and start customizing again. this time document your work and use SVN
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