I've uninstalled Time in Status plugin but a custom field named Time in Status remains on my system
Time in Status by OBSS does not introduce any custom fields or custom field types to your system. Even though the custom field name is similar, it must belong to another plugin. Some other plugins are known to create custom fields with similar names. For example, Jira Suite Utilities is known to have such a field.
I see some values as 0.00 and some values as a dash ("-") on my screen. What are those?
When report values are displayed on screen in Days, Hours, or Minutes; the decimal values displayed in the report are rounded down to two decimal points, for readability on screen. The calculation of the duration of a very short visit to a status (for example a few seconds) results in a value that is very close to zero and when rounded to two decimal points, the value actually becomes 0.00 . Such very short durations are intentionally left to be displayed as 0.00 because they are too small to be displayed above 0.00 but we want them to be distinguishable from non-visited statuses (which are displayed as a dash ("-") instead of a duration). If you change your view format to "seconds", you will see that those 0.00 values will show small durations. You can also export your data to a file. File exports include durations in full precision.
The values I see on the screen and the values in the export file do not match. The export file contains too many decimal points. Why is that?
When report values are displayed on screen in Days, Hours, or Minutes; the decimal values displayed in the report are rounded down to two decimal points, for readability on screen. On the other hand, users export data to a file to perform further calculations so we export data with maximum precision. Almost all spreadsheet applications allow you to format the values you see in your spreadsheet. You can use your spreadsheet applications' functions to display the values in any way you need.
