SAP BI4.1 Customization

Hi Expert,

Currently, we are using XI3.1 SP6 DESK reports which would be upgrade to SAP BI 4.1 SP2.

Below listed are some questions need to clarity on.

1. In BI 4.1, can we customize a webi report interface to add some clickable buttons
   (like DESKI .REA File)? If yes, are webi extension points the way to achieve this?
2. If yes to the above question, Can extension points be used to tap into LIVE user’s
   session to capture data/filter information? For example, can we create a
   clickable button which exports user’s report data into a txt file?
3. Is there some documentation available to know these extension point capabilities
   in detail?
4. Is there a risk of losing SAP support if we customize webi interface this way?
5. If extension points is not the way to achieve this, is there an alternative ? Is
   there a better way to achieve our functionality?

Please let us share the information on the above questions.

Thanks

Palanivel