I am still able to reproduce this.
I tested it again, and I'd like to rephrase.. "It's not renaming completely, its about CHANGE CASE"
Here's an empty project - https://dl.dropboxusercontent.com/u/48735785/Construct2_Issues/halo.zip
Try to rename the project to HALO or hAlo .. just caps out one word and try to save it.. it fails.
Please reopen the ticket :) .. sorry for late responds.. was travelling.