Guys i know, i missed something in the game.
I have 6 bases, but i can only build on 2 of them..
The game don't tell me why..

What am i doing wrong?

and about tracks, if i mess with the track i have alot of dificult to fix it.
help!
thanks

you can only build on bases you ave linked with tracks.

Also rememver you only need to link the bases, not every province. If you link a base all its province resources are collected.

The game auto builds minor tracks between resource provinces and captial provinces, however, to bring a captial province on line and enable base construction, you need to build tracks between the province and the nearest active captial province.

Remember, you want to use as little track as possible, so your best bet to start is Central Europe Base to Paris Base to London Base. London then gives you another quick jump around to Spain, from which you can hit North Africa. In the other direction, one option is to head via Moscow Base and split there to two other bases.