i have a similar problem. but i get different boxes. i had paint dot net before but i needed access to the effects and filetypes which on vista 64bit you need admin. access to change anything in the program files (menwhile im the only user on my computer.) so i tried saving in my documets where it worked but i couldnt open any PDN or PSD files meanwhile i had the plugin. i tried deleting it all and re-doing everything thinking something was corrupted but i dont know. anyway, here are the different windows i get. any help?
got this 3-4 times each try
got this once
final window