Unable to create large image file in iphoto

I make a lot of panoramic images by stitching together overlapping images with hugin in TIFF format, then edit them in iphoto and use it to export them in jpeg format for greater versitality of use. So far I haven't had any trouble, even with large images as big as ~25,000x2000 pixels and ~90MB file size.

However, I have come across a problem recently trying to export an edited version of a particularly large one - 38,062x1799 136MB file size. I can export an unedited version to jpeg without trouble, but when I tried to export an edited version it gave me an error saying it couldn't create the file. I looked around here for solutions and found the suggestion to check the file size in finder, it was zero. After experimenting I've found that the file size goes to zero as soon as any changes are made to the file, the edited image can still be viewed in iphoto, but does not display if you try to zoom in. I have tried making the TIFF file again with hugin to see if it is a problem with the file, but I also experience the same problem with the newly made file.

I am working on a Macbook air (1.7 GHz Intel Core i5, 4 GB 1333 MHz DDR3 Memory, Intel HD Graphics 3000 384 MB, Version 10.7.5 OS X) in iphoto '11 version 9.2.2 (629.40). Any suggestions for getting round this issue?