Here some basics for the image changer:
you can only compare with concrete values (value=5)
you can NOT compare with value ranges (value<5)
all values which are not mapped as option will show the default image
using floats for compare with a concrete value may fail, because of the decimal places (see Floating-point_arithmetic)
When you want to display different images for ranges of number, you can solve it like this:
use mulitiple widges iq-image
hide the image with WebIQ functionality (see picture below)
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