1-What is the function of ACS Depo?,and how can i send them to other planets?
2-Is there any limits for bulding's lvl. for ex. Metal mine is there a limit for it's lvl. apart from slots??,Can you build till 500 lvl.??

The ACS is used to consolidate friendly fleets for both defense and attack. Currently, the only thing enabled is the ACS Defense. ACS Attack is forthcoming.

Also, been getting word of errors with ACS Defend- to be sorted in another forum.

even my colonies

thesteel wrote:2-Is there any limits for bulding's lvl. for ex. Metal mine is there a limit for it's lvl. apart from slots??,Can you build till 500 lvl.??

The only limit is the number of planet fields. However, there comes a certain point where extremely high level mines are much better supported by solar sats than solar plants and that the return on high level mines is severely diminished. In other words, they become so expensive that their outputs do not justify the cost of building them. It could come to the point that it would take months to show a return on profits for a level 30 metal or crystal mine build.

even my colonies

Any planet can employ an ACS fleet as long as it has the ACS Depot.