[gmx-users] old and new versions of gromacs

[mohammad agha]

Dear Gromacs Specialists

I already worked with Gromacs-4.5.4. In the Gromacs site has been released new several versions. Has the old version (4.5.4) defects? Or are the new versions more complete? I want to continiue my simulations with 4.5.4, are there problems for it?
I compared the manual of 4.5.4 and 4.6.3. In the 4.5.4 there are 88 commands and in 4.6.3 there are 96 commands. 

If I want to install the 4.6.3 in ubuntu 12.10, what is the way of installation?

Please help me.
Thanks in advance.
Best Regards
Sara