Check this forum discussion
http://forums.pcwintech.com/index.php?topic=4298.0
Follow their IP check...
Your situation is probably like mine was until last year - I am on wifi connection to my ISP and for basic subscription it meant I was in effect on their LAN (ISP's LAN, my home router had LAN IP in its setting), that is I didn't have public IP.
What that meant was I could use internet just fine, but couldn't host a server which pple from outside could connect to. For example, teamviewer (tv) can connect to you because they use third party server that your tv client connects to and so others on internet can connect to you via that external server. They do not send that request directly to your tv client... but with mir server they have to and it won't get to you through your ISP (thing is that IP you posted is your ISP's IP, not your personal IP, that is external IP of your home router..)
Not sure if setting up a connection via some proxy server would help in this case, mir server is not as sophisticated as tv client, they have it worked out specially and I must say it works amazingly and very well.
I now pay a little more and have static IP and could host mir. If your ISP says you need static IP to host mir, than they know well what they talk about. Myself and others got confused by the way you formulated it because we thought that to host a server you can get by with dynamic IP, don't necessarily need static even if that's better. What your ISP means is if they give you public IP, it will be static (and static is of course better), wouldn't make sense for them to sell you dynamic IP (which technically they likely can't even if they wanted due to how wifi ISP works).