My only problem thus far is enabling the Color Effects options, e.g. Brightness, Contrast, Saturation, etc., dont work, and not only dont they work, they produce a blank, black or gray image, both in Preview and after processing. Other settings, e.g. Gray Scale, Border, etc, seem to work fine.
My real "complaint" is the lack of a white balance setting. I have hundreds of IR images that all need a subtle tweak in their WB, and a batch mode to do it would save countless hours.
Another great feature that the developer should look into is an "auto" function for the Color Effect settings. While no auto-setting will be perfectfor every image, there are several apps in the Store that have one-button fix that adjusts brightness, contrast, HSL, etc., yielding very acceptable results, certainly better than straight out of camera. Sadly those "one trick ponies" dont do batch processing.
Add it here, add WB, and fix the color settings and this would be a complete batch processor.