When you have all the surfaces the right way up I would recommend you to start figuring out an excellent tool called Edger2.
Now there are many (manually?) added condlines in your file which have bad control point.
This makes them show up to soon, or to late, and don't give the wanted result.
Delete all the condlines you have first. Add new ones with the tool.
Click on Tools.. and choose Edger2. This opens a menu of settings for the tool. All you need to start with are the 2 marked dropdowns.
If you choose Include Unmatched Edges the tool will add a red edge line where an edge line is missing.
Since you are working on a mesh divided in 2 halves it might be better to choose Exclude Unmatched Edges.
The other dropdown will set the scope for the tool.
Choose File if you only want to add missing lines in the file you're working on, or File+subfiles if you want the tool to search deeper in the part structure for missing edge and condlines.
Leave all the rest in default settings.
Click OK and the tool will add what is missing.
When you are satisfied with the settings you can use the quick button Edger2, next to the Tool.. menu, to trigger the tool to add condlines.
That button will use the settings from the Edger2 tool menu.
Now there are many (manually?) added condlines in your file which have bad control point.
This makes them show up to soon, or to late, and don't give the wanted result.
Delete all the condlines you have first. Add new ones with the tool.
Click on Tools.. and choose Edger2. This opens a menu of settings for the tool. All you need to start with are the 2 marked dropdowns.
If you choose Include Unmatched Edges the tool will add a red edge line where an edge line is missing.
Since you are working on a mesh divided in 2 halves it might be better to choose Exclude Unmatched Edges.
The other dropdown will set the scope for the tool.
Choose File if you only want to add missing lines in the file you're working on, or File+subfiles if you want the tool to search deeper in the part structure for missing edge and condlines.
Leave all the rest in default settings.
Click OK and the tool will add what is missing.
When you are satisfied with the settings you can use the quick button Edger2, next to the Tool.. menu, to trigger the tool to add condlines.
That button will use the settings from the Edger2 tool menu.