Guess it's true, assuming gets you into trouble. I assumed the settings were irrelevant since they were the same in both the working local site and the remote site. Sorry and here are the settings:

Title Value Action
Small Image Width 100
Small Image Height 80
Heading Image Width - Admin 57
Heading Image Height - Admin 40
Subcategory Image Width 100
Subcategory Image Height 80
Calculate Image Size true
Image Required true
Image - Shopping Cart Status 1
Image - Shopping Cart Width 50
Image - Shopping Cart Height 40
Category Icon Image Width - Product Info Pages 520
Category Icon Image Height - Product Info Pages 375
Top Subcategory Image Width 150
Top Subcategory Image Height 85
Product Info - Image Width 150
Product Info - Image Height 120
Product Info - Image Medium Suffix _MED
Product Info - Image Large Suffix _LRG
Product Info - Number of Additional Images per Row 3
Image - Product Listing Width 100
Image - Product Listing Height 80
Image - Product New Listing Width 100
Image - Product New Listing Height 80
Image - New Products Width 100
Image - New Products Height 80
Image - Featured Products Width 100
Image - Featured Products Height 80
Image - Product All Listing Width 100
Image - Product All Listing Height 80
Product Image - No Image Status 1
Product Image - No Image picture no_picture.gif
Image - Use Proportional Images on Products and Categories 1
IH resize images yes
IH small images filetype no_change
IH small images background 255:255:255
IH small images compression quality 85
IH small images watermark yes
IH small images zoom on hover yes
IH small images zoom on hover size Medium
IH medium images filetype no_change
IH medium images background 255:255:255
IH medium images compression quality 85
IH medium images watermark yes
IH large images filetype no_change
IH large images background 255:255:255
IH large images compression quality 85
IH large images watermark yes
IH large images maximum width 750
IH large images maximum height 550
IH watermark gravity Center