Switching resource packs crashes game

I expected to switch out of my Resource pack to the Default pack, due to an issue with font size

The game crashed upon switching to the default pack. However, restarting the game shows that it did, in fact, switch from the resource pack to the default. Switching from default to the resource pack will cause the same result; E.G, it will crash, and restarting the game shows that it did, in fact, switch packs.

This resource pack was converted from the JohnSmith Legacy Texture Pack for 13w05a using the Texture Ender program. The same thing happens when trying to switch to another resource pack, one converted by the Ender from the x32_Atherys_Ascended for 1.5 (texture pack version 1.2). I have not attempted any further tests with other converted packs. Both packs also exhibit the same font problems prior to the crash; as in the font is much too small and the kerning is way off. To reproduce I recommend downloading one of those two packs, converting them into resource packs, and trying to switch from default.

Also, apologies if this has been reported before, I'm really just trying out the new launcher's ability to directly report to this site.