One thing I've always wanted (and have asked about here before) was a way to edit the data inside VI files at a low level. Well I finally figured that out. I have here a tool that will let you open a VI, look at the individual blocks of data stored within, and make changes. Plus, with the power of private methods and internal settings, it can also convert VI's to a format where the front panel and block diagram are XML-based, so you can easily edit the raw representations of objects. Here you go. Run "Resource Editor.vi", select a VI (make sure you make a backup first if you care about it), and click Load to load its resources. Click "Load as XML" if you want to edit the front panel and diagram as XML. If you've edited the block diagram at all, make sure to click Fix VI Checksums. Then just click Save once you've made the changes you want.
EDIT: Second version is posted; this one should work in LabVIEW 2014, and fixes some bugs. I also added copy/paste buttons for the front panel and block diagram resources, since LabVIEW's built-in copy/paste function didn't seem to work for some reason. Note that if you edit the front panel or block diagram in the VI without using copy/paste (and the size is different), you need to update the size (first 4 bytes) as well. You can do this by clicking Copy and then Paste. Now this may not be too useful for you, considering it's not something you should use in production code or anything you don't want to break. (I say that a lot in my posts, don't I?) But if you're curious about how VI's work internally, it's perfect. This requires OpenG. Also, special thanks goes out to Thomas Zeugner for making VI Explorer. You know, that tool for cracking VI passwords. Turns out he figured out how the VI checksum (in the BDPW block) is calculated, which helped me greatly. Oh, one more thing, I do plan on improving it. I was just excited to share what I had. So keep in mind there may be bugs.
Latest version:
The latest version is posted on the tool's home page, here: http://flarn2006.dyndns.org/llvim/ Older versions:
Low-Level VI Manipulation rev2.zip Low-Level VI Manipulation.zip