Welcome.
With any forums, it doesn’t help to repeat the same post all over the place - it leads to confusion, fragmentation & duplication…
If you do cross-post, always make it clear and give links between the threads - and be sure to keep them all updated.
Is there another kind…? 
sierrawireless.com/productsa … eries.aspx
Yep - should be fine.
Not such a good idea.
Amazon may be cheap, but one reason for that is that you’ll get no support there!
I would strongly recommend that you seek to build a relationship with a local technical distributor.
Although C++ is, of course, possible it is rather a minority interest. You might find it easier to start with plain ‘C’.
To be precise, GPRS (an “overlay” on GSM for packet data)
Now that’s one that might be better asked in the Development tools forum - as it’s a specific tooling question.
The GL61x0 are based on the WMP100, which is now “not recommended for new designs” - so I guess that’s why it doesn’t appear in the latest DevStudio?
This seems like a bit of an oversight on the part of SiWi, since there are still plenty of products using it - such as the GL6100 
Look at the FCM (“Flow Control Manager”) examples…
Note that “Flow Control” here has nothing to do with “flow control” in the usual serial comms sense (XON/XOFF; RTS/CTS) - it is just SiWi’s name (inherited from Wavecom) for a “data stream” or “data source/sink”
Yes:
- FCM for serial data;
- Flash or A&D for persistence;
- WIP for sockets
Again, that’s where a technical distributor could really help you - by discussing your application in detail, and going through the options available.
You need the ADL User Guide - it’s usually buried as a PDF somewhere deep in the Dev Studio installation’s folder tree: Go to the top of the tree, and use the windows explorer search to find all the PDFs…