There's a reddit post for a proactive renpy timer with sample code. If a clock timer proves too difficult, then maybe have a decreasing counter for a limited number of exploration. Either way, 60 minutes may not be enough time to casually walk around given many narration states "several minutes" or "an unknown amount of time" in some form.
Below is some data you may find helpful. Excludes time spent walking.
Edit: For those lost in your playthrough. See #5 Speedrun down below.
#1 Casual Exploration: Clockwise. Follows narration.
Total searches: At least 15, closer to 23.
#2 Casual Exploration: Counterclockwise. Follows narration.
Total searches: At least 15, closer to 20.
#3 Helpers:
Total searches: At least 15, closer to 20.
#4 All keys on me:
Total searches: At least 15, closer to 23.
#5 Speedrun: All 4 sex scenes, 6 skills, 3 key parts, no detours.
Total searches: 11
- Brewery (leave), Pantry, Servants' Quarters (pants), Latrine
- Kennel, Barracks (all options), Kennel again, Pantry again
- Masters' Chambers
- Library, Lounge (mandatory), Study
It seems you can have each search take up roughly 3 minutes of the clock. Some areas fewer, some areas more. Similarly for scenarios. A casual run can fail this way. Best of luck, orangelo. Hope this helps ya.