That's OK, I'm happy to help, though i should point out my replies are only based on my experiences, so anyone else with chipmunks reading is more than welcome to chip in with their thoughts.
With the seeds thing, yes they can make a lot of mess. When you get yours try to keep them in their aviary for about a month, so they learn that that's the place to go to toilet, and bury/hide seeds. Seed storage is something they do all the time all year round. Given the chance they will try to hide seeds and nuts not only in their home but all around yours and often somewhere on you. Some owners try to control this by only letting them out when their cheeks are not full. But the way I look at is, they are still semi wild pets, and they have already made a compromise by living indoors, so most times I try to let them do what they do because it's natural. They only store dry stuff, so it's quite quick to clean up after them. However this would not be good if they went to toilet everywhere, I don't mind cleaning up seeds but having a pet that went toilet anywhere would not suit me, that's why I don't keep pet rats. Chipmunks will go to toilet in the same place, they will back in to a corner and do their business, so making it easy to clean. I found in reality that young chipmunks (up to about a year old) take time to get into this habit of using the same place. A youngster can have accidents, I've found a young chipmunk will urinate if it is frightened or very excited, so they're a bit like kids. Once they have matured they will use the same place as their toilet, and are either so used to me or bored by me they never have accidents when they are older.
I have twelve chipmunks, with about six out on free range at anyone time, I have about the same number of computers (bit of a nerd me), along with all the other gadgets a home has. Apart from keyboards and cables I've not had any other significant misshapes. But over the years I have altered the rooms that the chipmunks go in, mostly by de-cluttering of things. There is not much stuff out now that they can knock over or hide seeds in. But I hope you don't get the wrong idea about them, they would not just sit there chewing up any documents or bank notes you might have left out. They just like exploring, and have the ability to get to any part of the room they can see.
Let me know if you have any other concerns, as this is a good thread for anybody who wants to know what keeping a chipmunks indoors is like.