[UPDATE] I am using X2 2.8version and working on WinXP
I've tried to use the Reverse Proxy feature as it is a very nice idea.
However, when I am really trying to use it. It has problem.
First, it is ok, if I forward to some root path ( ie. '/' ), but then, it is not ok if try to access 1 level depth
Say, forward '/' from front end to '/' to back end.
This is ok if I try

http://mysite.test/

the result goes fine.
But, when I try

http://mysite.test/img/

It goes to 404 Error.
I tried on the setting many time, but no clue. Finally, I set a trap in the back end side with a custom 404 script. The myth being open, when I fetch the ENV, I got:

REDIRECT_REQUEST_FILENAME = D:\Test\mg
REDIRECT_SCRIPT_FILENAME = D:\Test\mg
REDIRECT_SCRIPT_NAME = /mg
REDIRECT_SCRIPT_URI = http://mysite.test/mg
REDIRECT_SCRIPT_URL = /mg
REDIRECT_STATUS = 404

This is obviously the first char got chopped. Then I try

http://mysite.test/xImg/

It's ok now, the "x" is prepared to "feed" the chop.
[UPDATE]
Also, whatever the way I try to put in the remote path, the tailing / will be chopped. That mean, if I forward a / from front end to /home/ at backend,
if I request

mysite.test/img

, this resolved url will become

http://mysite.test/homeimg

and I think this is VERY WRONG! In such case, I cannot separate the hosts under the same root with different folder, but to use a port to set a root to root forwarding
Will there be any patch for this ?