Assert failed when generating withdrawal proof

[moeadham]

Hey Folks, cool project. I tried it out but am unable to generate a withdrawal proof

Not sure if there is more I can do to assist, but this is what the js console throws when I click generate proof. I've tried with a few different subset data arrays. This is on the 0.01 pool

ERROR:  4 
withdraw-ec1e0be87fe32363.js:1 Error: Error: Assert Failed. 
    at 5718-05cb7a8cbfe9517c.js:1:119171
    at Array.forEach (<anonymous>)
    at io._doCalculateWitness (5718-05cb7a8cbfe9517c.js:1:118725)
    at io.calculateWTNSBin (5718-05cb7a8cbfe9517c.js:1:119759)
    at iu (5718-05cb7a8cbfe9517c.js:1:120703)
    at async Module.il (5718-05cb7a8cbfe9517c.js:1:120847)
    at async e0 (withdraw-ec1e0be87fe32363.js:1:5072)