I have recently installed El Capitan onto my MacBook Pro (5,1). I now notice that with certain applications I can no longer drag and drop a file onto the application icon (or alias) to force it to open. This no longer works with Photoshop Elements 10 and Preview, but it does still work with my copy of PS6.................curious, any thoughts? (I have recreated the alias's).
Try rebuilding the Launch Services database. There are a number of utilities that provide this service including OnyX, TnkerTool System, Cocktail, and MacPilot in rough order from free to most expensive. I am sure this can also be done from within Terminal, but I have never found or seen the necessary command.
I think that is one of those things you aren't supposed to have to do anymore but after one beta update my Open With list turned up empty. Repairing the Launch Services database restore it in all its glory.