Here's the code I use for creating custom, integrated pages on my site. Of course, there's also the .php file in the directory, but this is the template code.
Code:
$stylevar[htmldoctype]
<html dir="$stylevar[textdirection]" lang="$stylevar[languagecode]">
<head>
<title>$vboptions[bbtitle]</title>
$headinclude
</head>
<body>
$header
$navbar
<table class="tborder" cellpadding="$stylevar[cellpadding]" cellspacing="$stylevar[cellspacing]" border="0" width="100%" align="center">
<tr>
<td class="tcat">Custom Title</td>
</tr>
<tr>
<td class="alt1">
<custom HTML goes here>
</td>
</tr>
</table>
$footer
</body>
</html>
This has been working fine for me, up until last night when I tried to add code 177627 characters in length and it wouldn't save it (blank gray background within the admin console). I played around it with and found that it wasn't in fact a size limit like I thought, because when I deleted the code above and just left the custom javascript code (177627 characters long) that it saved it just fine (but of course didn't display properly without the code above).
Can you guys see why this could be happening? It's something with the code above that seems to be causing the problem...