Resolving Price Change in Inventory

there is nothing to resolve. Manager only calculates the average cost of inventory items you buy and sell. you can read about these in the guides @p4unger provided.

i am not sure where you downloaded the older version but the official website only allows downloading the latest version. you need to provide more details than just generally saying it is not working. so generally answering, recently there have been issues with the proper version of .NET framework not installed. you should update it if it is not updated to version 4.6.1 or higher. also, it would be better to atleast upgrade to Windows 8.1 from Windows 8 due to possible issues discussed in the below topic.