Version 1.3.4 makes updates slightly more robust. I've been noticing some strange behavior at the JPL raw images site in the last couple days; amongst other things, new index files may have been posted with earlier modification times than previous versions, which MMB wasn't handling well. This update downloads index files if they have an earlier modification time or a later modification time.
Right now there are a lot of sols marked "NEW" on the navcam section of the Spirit raw images page at the JPL site, and apparantly there were even more previously. I don't know exactly why that is. I haven't been seeing a lot of actual new images. This may cause some long downloads if you are just starting using the program. You can always stop the update and manually update from Exploratorium using the commands in the Update menu. Hopefully the situation at the JPL raw images site will get cleared up before too long.
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