Java or wxWindows Time Tracking

We require an intranet based time tracking tool for an enterprise company. The app needs to be cross platform as there are Windows and Mac users. The app will ask for a user code and project code and will begin tracking time. The app will need to track mouse and/or keyboard action to make sure the user as actually working on something. Over a given 5 minute interval the user will be scored with light activity, medium, or high. Every 5 minutes the active window only will get captured and uploaded to a server as a jpg file. Every 15 minutes a full desktop picture will be taken . There will also be a trigger on certain apps. For example, if the active window is the name of a game (solitaire for example) or Skype or some unapproved app, a screenshot will be captured right away and again after 20 seconds. All screenshots will be placed in a queue and uploaded at a slow rate so that the server is not hit to hard and so the user can keep working if there is no intranet. Some users take a laptop home, for example, and need to keep working without internet all night. Ideally the same person can write the server side code to accept the screenshots and place them in a directory. No complex server side is needed right now. The user code and project code do not require verification. The user should also enter a "sync" directory for the project. The directory and other inputs should be saved so that the user does not have to re-type them each day. The app should take an md5 hash of the directory that is the sync path and anything that has changed will be put in the upload queue. Some files need to be excluded based on a hard coded list. The app should update itself from the server if a new version is posted. The interface should be a simple small movable window that says "Working on: PROJECT". That's it. If the user goes to No activity for more than 30 minutes change the text to read "Click to continue working" and then when the user returns they can click it to get started again. Time is critical, I need this very fast. Indicate the word ZOOM as the first word of your response to me.