Coupla problems with protecting folders

I've just installed aMember Pro and all is going OK apart from a coupla things:

1. When I want to protect a folder ... and press the "browse" button, I get the following error message:

"Warning: opendir(\D:\Domains\webdemise.com\wwwroot\amember\): failed to open dir: Invalid argument in D:\Domains\webdemise.com\wwwroot\amember\admin\protect.php on line 278
Cannot open directory: \D:\Domains\webdemise.com\wwwroot\amember\"

Anyone know what causes this? I end up 'manually' entering the path ..

2. My site is hosted on a Windows machine which has IIS (not Apache), so it seems that htaccess doesn't work. When selecting the protection method, for all methods (except htaccess & php include) - I get the following:

"(Unable to fetch result of test from http://www.webdemise.com/amember/data/tests/mod_rewrite/1.php. Read FAQ item regarding this issue) "

I read the FAQ and it mentions that cURL should be installed - I just want to confirm that this (whatever it is?) can be installed on a Windows host before I approach my Sysadmin? At present, the only password protection I can use is php include ... which really doesn't suit my application.

Thanks in advance for any help.

Pete