MS Project and Project Management Integration
I thought to create this document because there is not enough information available at one place to guide while doing required configuration and troubleshoot the issues. Following are the points which will help to see the standard integration of Project Management with MS Project and troubleshoot issues.
This document doesn’t include the configuration details related to field mapping between MS Project and Project Management.
Below you can find Details for:
Export Project from Project Management to MS Project
Import Project from MS Project to Project Management
Update current Project vs. Create Simulation Version
Project Management Integration with MS Projects#Field Mapping
Project Management Integration with MS Projects#Tips
Export Project from Project Management to MS Project
Select the Project in dashboard and click on export 
Choose the application as Microsoft project
Click on Check
Click on Export.
Enter the file name and click on save
Import Project from MS Project to Project Management
Make sure that the MSP file is saved in security list folder or sub-folder of that particular security list path.
Select the Project which you would like to update from MSP and click on Import Project button
Select the application as Microsoft project
Select the file which you would like to upload in cProjecs PPM) 
Click on check.
Click on import
Update Current Project vs. Create Simulation Version
Depending on the setting in the project-type the current Project can be updated or a Simulation version is created (Setting for "Target Object").
Open the project type in detail and check the parameter "Proj Type" under "Project Integration":
- User-Defined Selection
- Always Overwrite existing project
- Always Create Simulation
By this customizing setting it´s also possible to define a preselection by using "Always Overwrite existing project" or "Always Create Simulation". Then the parameters cannot
be changed while importing the project from MS Project in the project.
The check is done in the following coding:
Webdynpro: INM_TRANSFER
COMPONENTCONTROLLER
PROCESS_IM_PROJECT
Field Mapping
The field mapping configuration can be called in customizing under: SAP Portfolio and Project Management -> Common Functions -> Import and Export of Project Data -> Microsoft Project Integration, you can achieve integration of PPM with MS Project.
Allowlist Configuration
Also, you have to review the Regional Settings of Microsoft Windows and install hotfix of MS Project versions.
Hotfix Package for MS Project 2007: http://support.microsoft.com/kb/981732/en-us
Hotfix Package for MS Project 2010: http://support.microsoft.com/kb/2075992/en-us
Tips
Troubleshooting and Debugging Guide: MS Project Integration (Tips)