I'm not aware of any built in commands to do what you want, but this can still be done programmatically.
First thing is to download document 1465, which is the OptoMMP Protocol Guide which will give you all the memory map addresses for the I/O units. This is a great reference when venturing outside the built-in commands.
You will want to use the I/O Unit Memory Map Commands to read the addresses for the analog unit "counts". You can get the counts for all analog modules with something like this command:
ReadNumTableFromIoUnitMemMap(64, 0, ioYourIOUnit, 0xF0600100, ftResults) //Edit: Using Bank read
I got this address from the Analog Bank Read section of the protocol guide. You will need to know where you point is located on your board (or you can figure this out programmatically by looping through the point names in the configuration section - this will take some more advanced programming).
ftResults will contain 4 values for each module on your board. The values are in "counts". 25,000 is the max value for input counts - so if you want to see when you are withing 90% of max value, then you would look for anything above 22,500. (Details in the protocol guide, Overview of Programming, Using I/O point features, Scaling).
Edited to fix some errors in how the analog bank works.