Here are some words from the MWS-developer himself:

It is probably a temporarily problem with the Ovi Store. But I recommend you to use Remote Multi Drive. Remote Multi Drive can do more than Mobile Web Server and works with IE.
And Remote Multi Drive will get lots of updates in the near feature
(multiple file and folder upload with java supported browsers).
Mobile Web Server update is hard, because it is very different from
Remote Multi Drive (uses threads instead of event driven methods).

Regards,
Istvan