Hi,
Well, SSO on the Linux system can be achieved by following the SAP note:1965433.
SAP says it is not fully supported because it requires expertise in multiple technologies and also an involvement of the experts of those technologies.
While working on the third party authentications, I have configured this for many customers and it worked for them as well. However got many troubles 
You just need to understand all the technologies well which all are involved in this configuration.
If you are sure you can do it then you can go for it. Or else you can follow what Mani has suggested.
I would suggest you to try it on your test server first and if it works then go for the other servers.
- I believe the BW users are already configured with BILaunchpad and they can login successfully.
- If Yes then you would need to configure Windows AD users into Business Objects.
- After mapping AD users make sure they can login using Windows credentials.
- You would need to map all the BW aliases to AD users in CMC if they need SSO to BW as well.(This would be for reporting purpose)
- Once the AD users can login manually to BILaunchpad you can configure SSO for them.
I would not be able to comment on the Netweaver SSO 2.0 part/configuration since it is not clear how you have configured NW in your environment.
Hope this helps. If you run into any issues then we are always here to help you 
~SwapnilY