Glum Buster is a charityware puzzle adventure game which took CosMind four years to create with the Game Maker engine. Comparisons to Seiklus are likely, since both share more than a couple of similarities in terms of sparseness in storytelling efforts and a heavy emphasis on exploration.
Besides using the cursor keys for movement, you would need to interact with objects scattered around the environment quite frequently using either or both mouse buttons. Holding the left mouse button fires a red shot at whatever it is that you're pointing at, while pressing the right mouse button allows you to activate certain objects or attract them towards you.
The solutions to most puzzles are usually contained in the same room, although some locations may span several screens long and wide. This is where one of the major flaws with Glum Buster rears its head, because if you encounter any difficulties solving a particular puzzle then you will be stuck at that area until you figure out the right thing to do.
Nevertheless it's one of those rare efforts that has to be played, especially if you have any fond memories of the first time you were introduced to Clysm's masterpiece. (source, interview)