[Lawrie]

Hi, 
I have the custom field filled with numbers. 
Bus if i open een collection it automatically gets the same order as the songs tab.
So im not sure what you did.

What i did: 
Librabry settings: Title format
%CUSTOM% %TITLE%

Unter sort: custom
Use formated title for sorting
By field Custom

G'day Chris,
thanks mate.
I already have something similar set up:
%TITLE% %CUSTOM:[${CUSTOM}]% %CUSTOM_GROUPS:[${CUSTOM_GROUPS}]%

This displays the song name/title, optionally followed by the Custom field and the Custom_Groups fields in [ ] brackets if they are populated.

I find that generally I prefer the song name as the primary sort.  It's only occasionally that I would find it useful to sort on the Custom field, but when I did it would be VERY useful.