Please note, according to our license mechanism, licensing code for specific APIs should be processed at first and before using any other Aspose .NET APIs in your program and it should be processed at least once in whole application life cycle.
You may place the licensing code where it should be processed first and only once in your application life cycle. For example (in a .NET application), if your application is server based (e.g. a corporate web site or web service where clients would be accessing it via some browser types etc.) you may place the licensing code (instantiate License object(s) for each API and set license accordingly, etc.) on some events like Application_Start or any other section, etc., because licensing code is only required to be processed once in the whole application life cycle. It is optional and is not recommended to process the licensing code multiple times for no reason.
Please post your queries regarding your license (you purchased) and its type in Aspose.Purchase section and one of our sales staff member will assist you soon there.
I am afraid you have to set license for each Aspose for .NET API individually. You are already doing ok to individually specify and set license for your desired APIs in Aspose.Total for .NET.