I have the task to make this work, and thought that the best way to proceed would be to put a 'secret' utility file on the webserver. Then from my local software I make a http request that passes all the information needed to create a new user. For the moment, lets ignore the security issues related to this

Basically thats pretty clear, but there are some hurdles and I can think of two ways to go from here:
1. Place my utility file outside of cmsms and make it do all the mysql database updating needed to add a user. This would require me to either write a lot of code or to copy a lot of the existing code. And if i succeed I'm not sure I got it all right, so I don't like this variant.
2. Place my utility file inside cmsms which requires me to login? I have seen the file modules\FrontEndUsers\function.admin_importusers.php and think this is a good starting point to base my code on.
Is there a third way to do this? Can I log into cmsms at all if I'm requesting url's programatically (not using a browser)
Comments very much appreciated,
Sune
(version is 1.2.3)