I recall a discussion, I believe between Magician and CorePC about the Mesogea master file and the recurring error message in the CS that states that bad forms encountered loading the master cannot be removed.

I open TES4Edit and load the Hiboriamain.esm (Mesogea landmass) and after about ten minutes the entire thing is loaded. I am then presented with a screen and a load of options? What exactly am I looking for to fix this bad forms error?

I had this error as well in my esm. The reason was that someone moved or deleted objects in the render window that only existed in the old version of the esm he was using. In the new up to date esm I was using the objects were already deleted. When I merged his esp into the new esm the error came up since the esp did something to forms that didn't exist anymore in the esm the esp was merged to. You can delete these forms with TES4Edit, but I don't know how to find them since CorePC did it for me. Maybe ask him to do it for you.

Sure will. I'll give it a go. COREPC, if youre listening here, help! The mod throws out no errors in game, there are no problems running it, but you never know......