Was this fixed? I have the same issue.
1) If you use the price attribute in the backend it also uses the value as a money amount.
2) In the frontend it shows the currency sign.
Isn’t there a simpler way to use the field as integer or decimal?
Lately we added such feature to our Improved Navigation module. With its help you can create decimal attributes and display any measurement unit you need. Please see http://amasty.com/improved-navigation-price-slider.html for more details. Will this work for you?