Potential issues with presolve: incorrect 'optimal' solution and incorrect infeasibiliy detection

[deryaozyurt]

Greetings,
I have two problems where HiGHS returns incorrect results. In the first problem the solution returned is suboptimal and in the second it is incorrectly reported as infeasible. Turning presolve off avoids the potential issue(s).
TwoProblems.zip

[jajhall]

With latest:

• First (1725a.mps) is incorrectly identified as infeasible in presolve, and solved correctly with --presolve=off. Error is in reduction 851/861
• First (1725b.mps) gets wrong optimal objective value of -4987010.44031 rather than -4987029.63936, with the latter obtained when --presolve=off. Error is in reduction 850/971

[fwesselm]

@jajhall I am having a look, if that's Ok

[jajhall]

Sure, I've got marking to do for a few more days