Error in Srb2Doombuilder.

[ThunderNova]

I'm currently working on the map seen on my Deviantart, but there is one problem: Something is wrong with either my computer or Doombuilder.
Now, what happens? Whenever I go to "Scripts" and select "Edit MAINCFG Lump...", this screen comes up:

Clearly, there is an error, but I don't know what's wrong exactly. I never had this error before, and since I am using a new laptop, it might relate to this, but I've read through the SRB2Wiki D.B. Tutorial many times, and have done everything related to setup right.

If anybody could help, it'd be great.

 

[Dark Metal]

Fafulfan knows...http://mb.srb2.org/showthread.php?t=34589
but this guy tells it http://mb.srb2.org/showthread.php?t=33459

You either are missing the file or you can try running it as administrator by right clicking the Doombuilder Exe file. If that worked than right click, go to properties, got to compatibility, than check the option that talks about administrator.