Can't install/update Mtb Project v 4.4.0 or up

Hi All...anyone besides me having problem updating to v. 4.4.0 and up?  I have Android 7.0 on my phone, so should be compatible.
According to description this app should work on Android 4.2 and up.  Something's not right.  Thanks.

Sorry about confusion...tried to update v 3.4.0 to current and did not work.  Then confused version with Mtn Project.  Have to do more checking.