Several things you should do:
first, be sure to upgrade to the current nightly build of zenphoto. Search is a new item, so some problems may have been fixed.
Second, try out the basics, like search, on one of the distributed themes. If it works there, then the problem is in what you have done.
#1. For your first page of 6 images, you will have to code that yourself as zenphoto does not have such a page currently. How are the images to be selected? If you are using the next_image() loop as in album.php you will get back the number of images as defined by your configuration images per page option. If you want a different number, your PHP has to implement that.
#2. Send page to a friend is not a function that currently exists in zenphoto. You can code it yourself. If you do, please share the code. It could make it into the 1.2 release.
#3. Search will return both albums and images. However, the two are independent. If you do not wish the albums then omit the next_album() loop on the search page. If you do want both, and want them to share a page for the transision from albums to images, you must so indicate by the [i]firstPageCount[/i] parameter to next_image(); If you do not supply that parameter, albums and images do not share a page. Visit http://testalbum.sbillard.org/ You can search for [i]find, searchtag[/i] and see a proper working search result.
#4. Not sure where this occurs. Some themes modify the number of images shown to fit with the format of there theme. For instance, effervescence+simpleviewer will always show a multiple of five images because there are 5 images in a row the way the theme displays them.
5. visit http://testalbum.sbillard.org/. There you will see working title display on rollover. If titles are set in the HTML, they will rollover. (The above URL is running the standard effervescence+simpleviewer theme. It has title rollover.