Trouble adding videos or photos to a page

Hi all, I'm very new at this so my problem is likely operator error but I am only sometimes able to add a photo and totally unable to add a video to my learning object.

I successfully added two pages with text and a photo (using the advanced image insert) but all of my other attempts to add text and a photo were unsuccessful. Neither the text nor photo appears when I publish or play the object.

I was completely unsuccessful inserting a graphics and sound page, video page or YouTube video page. None of these showed my text nor media when I publish or play the object and I checked to ensure that I am using jpegs and .flv files.

This has always been a problem from the beginning but it appears to be installed correctly. Can I (and should I) delete the plug in and re-install it. Would I lose all that I've already created? Is there anyway to save what I've already created before re-installing the plugin?

Lastly, is there a way to insert multiple pictures onto a page or can I only insert one photo per page?

What have you installed? Is this the word press plugin? Xerte Online TOolkits? Xerte for Windows? Where have you installed it?

I installed the Wordpress plugin.

is the USER-FILES folder writable?

Not sure what that is, where that is or how to find the answer to your question. Please advise.

try changing the names of the files - the WordPress script checks for various file names and it can dislike certain file names