i need some help

[MinsterOwns]

I need to know what unable to update edge (red) means in tool. thanx

[Arbiter Elite]

???

[MinsterOwns]

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\Program Files\Microsoft Games\Halo Custom Edition>tool structure levels\cityp
ark citypark
Couldn't read map file './toolbeta.map'
building intermediate geometry...
building collision geometry...
### ERROR couldn't update edge #41 (red).
### ERROR couldn't update edge #40 (red).
### ERROR failed to build collision geometry.
### ERROR failed to import collision bsp.

C:\Program Files\Microsoft Games\Halo Custom Edition>