Tag:amenity=hospital wiki page:
So it's missing an image. Why don't I add one when I've come back from dinner?

I added an image of mapnik showing one hospital icon. There is room for improvement I think but it will do for now: osm.wiki/Tag:amenity%3Dhospital

Observation: Wow! I'm impressed, mapnik has already updated the buildings and the hospital I added a few hours (or many minutes) ago!

2nd Observation: I did too many things at once, and an edit made to the interpolation way, caused JOSM to refuse to upload my new additions of the addresses. I'll take a rest(my primary way of solving problems ;) , and then return here to try to solve this mess. (Even by getting the new version, merging it with the layer I'm working with , is not working).

I'm afraid I'll lose data this way.