Digital potentiometer, initial (wiper+start position) resistance compensation
The limiting current is established when the Ilim input exceeds 800mV, so you can simply make an amplifier to amplify the voltage. 







simulate this circuit &ndash; Schematic created using CircuitLab

It should limit at Iout = \$\frac{0.8V\cdot\sigma}{R_S\cdot 0.001}\$
where \$0\le\sigma\le 1\$ is the digital pot "rotation"