Time to try another download.
This time, get driver 2.1.2.166.xxx and install it as before.
It MAY help, it may not, but it's worth a try.
If it doesn't help, reinstall driver 2.1.2.135b (It's the most stable of ALL HCF drivers, even though it's a little old).
If it's no better, try putting: +MS=K56,0 in the extra settings box (take the other out).
If that helps, but you still disconnect, try this: +MS=K56,0,,,,56000;S10=50S11=50
I've got more suggestions, but let's start with this. Cheers,
Jim