David,
I disabled AJAX completely and I'm able to create a new form and I no longer get ""errorSys.WebForms.PageRequestManagerServerError Exception" when trying to to change the image. But of course with my luck, I do get the form message that the file format is not supported once I click on "change image." And, I am no longer able to save the form.
There a ton of variables to deal with, like my DNN version, upgrading the forms, etc. So as to not waste your time - because maybe it's something on my end. Even if it is not, I want to be able to provided concrete details before asking for your time. So I am going to start with a new clean form and try to get things working.
If I can't get things working with starting a new form from scratch, I'll revisit this post and provide an update.
I truely appreciate your time. And just so you feel the love, I'm going to put a post in about a cool little feature I've implemented with Dynamic Forms & SQLGridSelectorView 4.1 (by Tresselworks) - it's a zip code radius search.