Shareware:
- Cannot do Auto-Scan
- Won't display Text for all Fault Codes
- No Basic Settings (so no TBA, Xenon levelling, etc or checking timing on TDI's)
- No Adaptation Saving (so no changing of locking/lights/horn behavior)
- No Output Tests
- No Tech Support from Ross-Tech
Limitations of 311 and 409 even if Fully Registered:
- No Generic OBD-II
- Won't work with CAN-Bus vehicles
- Fewer fault code definitions and label files
- No built-in Activation (you'll be limited to a single PC)
- No Advanced Measuring Blocks
- No Acceleration Measurement
- No Automated Service Reset
- No Session Log Capabilities
- No Support for Guided Readiness Scripts
- No Optical Bus Diagnosis
- No Battery/Gateway Coding/Long Coding Assistant
- No (Automatic) Updates
- No ECU Mileage Reading (EDC15/16)
- No Support for Windows Vista and Windows 7
...and some more minor things as well.
To answer your 2nd question you may wanna take a look at our FAQ, specifically
3.7 How do I permanently move VAG-COM from one PC to another?