As of now the max number of hours you can set is 9999 (aka 4 digits). I think this limit should be removed because some idle games can get well over that limit (if they take into account the time spent offline, like Cookie Clicker does (I personally have 530 days and 17 hours for a total of 12737 hours because I started playing it a few years ago and I'm unable to add time entries because of that))

Also, the achievement:

There's really no hard limit to how long these achievement names can be and to be quite honest I'm rather curious to see how far we can go.
Adolphus W. Green (1844-1917) started as the Principal of the Groton School in 1864. By 1865, he became second assistant librarian at the New York Mercantile Library; from 1867 to 1869, he was promoted to full librarian. From 1896 to 1973, he worked for Evarts, Southmayd & Choate, a law firm co-founded by William M. Evarts, Charles Ferdinand Southmayd and Joseph Hodges Choate. He was admitted to the New York State Bar Association in 1873.

Anyway, how's your day been?

(also from Cookie Clicker) does not fit in the goals (doesn't save) but that's something I understand

Both of these issues have been fixed :D

Thank you very much!