those are hooh's coom studio items, they are not dynamic and has to be placed and attached to characters or other studio items. it also features a shader with transparency that will help it blend (get soft edges) such as this. to add them go to "add>search" and look for "coom", then select the item from workspace to the right and click on the "material editor" icon at the bottom of that list, when it's open, scroll down for the shader settings and change the values as needed.
there should be a plugin for POV but i am not sure of the short cut, (maybe control+P) check the plugin settings (F1).
there is a fan translation version, check it out
here, i am sure there are updated translation as that link was a bit old so please check out the discord or gethub first.
it could be as simple as a too long game path, also 4.1 is a bit old now, redownload the DX r3 repack version.
earlier, somebody had this error and deleting the torrent (or removing it from the client) helped them to fix it. it is as if the torrent client is still using the file while you are trying to modify it. just make sure that the download is complete, move it to another folder and delete both torrent and content from client.
i still can't figure this out as well, it doesn't happen to all clothes all the time but it looks like some DHH light settings have a problem with skinned clothes that uses transparent shaders, running the game with DHH is off will fix the problem, you also can change the shader to AIT/clothes but you will lose the transparency. also try using other DHH presets.