Employee Scheduling Program Gantt Chart

I'm trying to create an Employee Scheduler. I want my employees (1 technician per row for a total of 10 rows) in the 1st column then the monthly calendar to the right (1 cell/day). That is what you'll see when you open the worksheet. Then, down below I set up my Data Area where I input my project, start date, end date, technician (where each tech is assigned a unique number), and other data across a row of cells. This could be infinite (or at least up to the very last row).

I modified a free Project Scheduler I got from XL-EasyGantt to become my Employee Scheduler but am having some difficulties getting it to do what I want. The project Scheduler basically works by entering (on the same row) the project (or task), the start date and finish date and then the cells get automatically filled in across those dates. This allows for overlapping of tasks but I want to create an Employee Scheduler so it doesn't allow overlapping or schedule a technician to start a new project before he/she has completed the one their on.

The main function which is in each cell of the monthly calendar is as follows: =IF(OR(AND($G28>=K$4,$G28<L$4),AND($M28>=K$4,K$4>=$G28)),IF(AND($E11="x",$M28>=K$4,$M28<L$4),"x",IF($E11=".",".","..")),"")

My problem: I want to be able to look at the Main Schedule and see when each Technician is scheduled for a job (or multiple jobs) for any given month. I want the function to look in my Data Area and assign the start date and end date of a project and the corresponding technician number and fill in the date cells across from their name in the Schedule above.