Hi
I tested the last "nightly" (july 3rd) on devuan ascii - the installation requires lots of packets I had to install manually (this is not common in i-mscp) - and at the end I hat to install PHP - but the only PHP I got from devuan ascii (is equal to debian 9) is a php 7.0.x - which is "to old for i-mscp...
Which version you tried to install exactly? Give me the exact link you used please I'm asking that because I'm pretty sure that you tried with the wrong branch... The github branch to use is https://github.com/i-MSCP/imscp/tree/1.5.3-maintenance.