URL Rewrite

We are using a product from Helicon called,  ISAPI_Rewrite 3

we have two websites on the same domain.  One HTTP port 80 and one HTTPS port 443.  When an internet requests comes in to our server, this ISAPI rewrite, evaluated the request to see if it is a port 80 request or a port 443 and then redirects the request to the appropriate website.

However this product doesn't work on our Windows Server 2012 R2 servers.  Microsoft has a tool called URL Rewrite that appears to do the same thing using IIS8.

I am not sure how to develop the rules scripts to make this work.  Examples that I have seen, seem to look very close to the Helicon rules.

What is the scripting language used in URL Rewrite in IIS 8 and are there any resources that would describe what these scripts are doing.

Here is an example of our Helicon Script:
RewriteCond %{HTTPS} ^.*on.*$ [NC]
RewriteRule ^auth/login(.*)$ http\://www.ourDomain.com/auth/login$1 [NC,R=301,L]


RewriteCond %{REQUEST_URI} !^/(?:Magic94Cache|Magic94Scripts|pl|ProPartnerProgram|samples|reports|reportsmgm|uniBCCache|uniRIAApplications|uniScripts/|web_pro/|web_mgm_pro/|wsScripts|aspnet_client|charts_cache|control|images/|js|Marketing|New_Site|ProPartner|Scripts|video|web_test_pro|web_trng_pro|web_training_pro|auth/login|ga-isapi/) [NC]
RewriteProxy (.*) http\://192.168.200.10/$1 [H,L]