From the following error message, your issue appears to be the caused by some machines not having the TMP and TEMP environment variables set correctly.
	''Error: Mercury File Transfer: Request for D:PCHostTempbrr_ZZZ.753netdirDEFAULT_Test_38Run_38res38sample209p_6.eve, but the file or directory does not exist. [MsgId: MERR-51992] [MsgId: MERR-51992]''
Please verify that on each of your PC components, that the environment variables are set correctly. This would cause a test results to fail to collate in Performance Center: 
	1. Set TMP and TEMP environment variables on all PC components (PC Server(s), PC Hosts and Standalone Load Generators for the System User (Default: IUSR_METRO) and the system:
	
		a. On all PC components within your ALM-PC 12.63 environment, log in using the System User account (Default: IUSR_METRO), and change the Environment variable for the ''User'' and ''System''.  Example:  C:/Temp and C:/TMP
		
			i. Set the ''TEMP'' and ''TMP''  folder location
			
				? Create a folder at the root of the local drive and name it TEMP
				
				? ClickStart, and navigate to Control PanelAll Control Panel ItemsSystem
				
				? Select Advanced system settings
				
				? In theSystem Propertiesdialog box, click the''Advanced''tab
				
				? ClickEnvironment Variables
				
				? Repeat the following steps for both the TEMP and the TMPUser variables:
				
					® In theUser variableslist, select the TEMP variable, and then clickEdit
					
					® In theVariable valuebox, typec:TEMP, and then clickOK
					
					® Repeat steps a. and b. for the TMP variable, if it exists
					
				? Repeat the following steps for both the TEMP and the TMPSystem variables:
				
				? In theSystem variableslist, select the TEMP variable, and then clickEdit
				
					® In theVariable valuebox, typec:TEMP, and then clickOK
					
					® Repeat steps ''a'' and ''b'' for the TEMP variable, if it exists
					
				? ClickOKtwo times to close theSystem Propertiesdialog box