Re: Image Gallery Problems
scribbly, to ensure that you get rid of the potential problems with mixed charsets, please, run the Upgrade again for tiki 5.3 (yes, I know, it's your version, but do that again, after you have a db backup of your site for extra security), and follow the steps at:
http://doc.tiki.org/Upgrade#Fix_the_encoding_issue
you might be suffering from that issue, which is known to break image references in the database...
And for some reason, new installations with Tiki up to 5.3 (included) didn't check the case that the db might be in another encoding than utf-8, and at a normal installation, tiki didn't check for that (no it does in tiki 6.x, afaik).
And welcome to Tiki community! 
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