Bh I work as an editor, correcting typos etc. last week my computer just shut down on me and i lost about 100 pages of work. I have already been paid for these pages; however I must make up for the lost work. in my case it is a דבר האבוד כפשוטו :)
My question is: if I am working divrie torah plus it is not for direct pay (rather if i don’t make it up i will have to return the money) can I do such work on chol hamoed?
A דבר האבוד means that if you don’t do the work on chol hamoed it will cause you a loss. It doesn’t mean to make up lost work, unless the fact that if the lost work is not made up by working on chol hamoed you will lose your job, or will incur a fine etc. Therefore unless this is the case you should not do it on chol hamoed. There is no specific heter because you are working on divrei torah. We only find that one may write down divrei torah that will be lost or forgotten if they aren’t written on chol hamoed because then it is a davar ha’aved, but otherwise divrei torah is not a heter to do melacha on chol hamoed.
Aside from this, your situation has two factors that would give it more reason that it shouldn’t be done on chol hamoed. It might be considered a maaseh uman- a professional job, depending on what level editing you are doing. Editing is a professional job and needs considerable skill, therefore it might be considered a maaseh uman. The second factor is that you are being paid for the job. Even though you already received payment for the work, the point is that it is a paid job.
H-shem should send you a shefa of parnossa and harbotzas hatorah.
O:CH 545-1&9, 542-1, M:B 545- 46& 47.