>> "In the documentation you mention that it is better to create a TFS on your infrastructure, but is this available already?"
Soon. No hard date.
>> "When we are using Named-user licensing for some product keys, is there a method that the client's IT department can enter the usernames or import them (sometimes many hundreds). "
No. You would need to implement that using our web API. Or, take the names when they purchase the license.
Or just not limit it to specific usernames.
>> "When we are using per seat licensing, is there a way to find out how many users are logged in (kind of statistics), but also a kind of log to see the average usage?"
The customers will be able to see broad numbers. You will not be able to see anything.
With the hosted version of TFS the user will be able to see real time information.
>> "What is the best way to cope with clients with a (non-persistent) VDI environment (for both TurboActivate as TurboFloat)?"
Always use TurboFloat on VMs / containers / hypervisors / sandboxes and every other word/rebranding that exists for VM.
>> "For the future; we are planning to have about 5 applications, some of the companies will have a mix of apps for a mix of users. So eg user1 is using app1/app2 and user2 is using app1/app4 etc.I understand that we should define various products for this, but is there an easier solution e.g. to prevent the client has to maintain 5 different TF servers etc."
Custom license fields: https://wyday.com/limelm/help/license-features/
>> "6) I assume we can use both TA and TFS in our application. First check if there is TFS, if not then ask for email/key for activation via TA?"
Yep.