Things like this are easy to fix.. Just create the folder name and put them in there.. A while ago there was  some change/bug, but I ran into this problem myself with some older versions of different skin objects. There was a change in the name space, where skinobjects were being placed. (That's often what you'll read as a breaking change in dnn.. well one of the problems)  And we resolved it by creating the folder, that is was calling for,  in the right place, and using ftp to move them there and the error disappeared. 

You see, skinobjects from my understanding behave differently to modules - they aren't in the SQL db, but use DNN files, ascx files, images & such and a dll file to run, and while installed using the modules way, they are placed in the host/module definitions/skinobjects section at the top of the module definitions page.

I have been guilty of not installing, but using FTP to place them in the right spot. (I had to do this when I had a couple of sites I was working on and had ftp access, but no host access to add the skinobject.)  And this solved the problem.  Not saying it will solve all, but has solved them in my instances.

Nina Meiers