• Whether it is okay to present the duration of tasks in days vs. part of days (e.g. 0.2 days for certain tasks)? Whether project schedule will be okay?

• Whether it will be okay to use lead of 1 day for two activities that are having duration for 1 day each and FS relationship? I tried to do that but it appear that both the activities are ending on the same day?

Whether it is okay to present the duration of tasks in days vs. part of days (e.g. 0.2 days for certain tasks)? Whether project schedule will be okay?

Yes, durations can be entered in any mix of units (minutes, hours, days, weeks or months). Underneath the hood, duration is stored in minutes.

Whether it will be okay to use lead of 1 day for two activities that are having duration for 1 day each and FS relationship? I tried to do that but it appear that both the activities are ending on the same day?

That is correct. Let's say Task 1 has a duration of 1 day and Task 2 has a predecessor of "1FS-1d", or in other words, Task 2 starts 1 day before Task 1 finishes. Since Task 1 only takes 1 day, Task 2 starts on the same day and since they have the same duration, they finish on the same day.

As Rachael has said you have a range of units you can use for duration. The only thought is that showing xh is nicer to read than 0.2d :)

If you are starting to use fractions of a day I would change the date settings to show time as it can be confusin g that a 1 day task has two dates as it starts on day 1 but finishes the next day because it didn't sart at 08:00 on day 1.

To show a lag between two tasks it would be done as task 1 is dependent on task 1 using 1fs+1d.

When I see this in plans I do always ask if the plan is "hiding" and activity. For instance I often see Issue Document for review linked to modify document with a FS+5d. This is a reasonable timeline but I always suggest that the Review task should be seen on the plan as A) this tells the story more clearly to someone reading the plan B) it is easier to adjust the duration of a task than to mess about in the linkages and c) resources can be applied to the review task to present a more complete view of the project.

One other thing to consider is "is the relationship truely FS?" I often see people using a FS where a SS+lag would be more representative of the true relationship