Here's the behavior I'm seeing in the current version of Rocket:

• If I drag and drop a block to another block location (except the first position) everything is fine. The block is saved in its new location and all other blocks display as intended.
• If I drag and drop a block to the first position by dragging the block onto the block already located in the first position then everything is fine. The block is saved in its new location and all other blocks display as intended.
• If I drag and drop a block to the first position, but drag the block above the block already in the first position, the block I moved displays at the top while all other blocks below it disappear. Upon a page refresh the blocks all display in their previous order except the one I tried to move. It gets moved to the end (or bottom) of the list of blocks.

If I then check the entries in mdl_block_positions I find that the weight for the block I was moving is to 6 or some other high number.