When i am working in large model, i will open the same model in read only mode by open another solid works in the same desktop. If i update one part and if i want any measurement in parent assembly, i will go to the read only model, reload the particular area and get the latest measurement. By doing this way, i can save the model loading time. Today, i faced one difficulty that i created one new sub assembly by combining two already available parts. To measure, when i reload the read only file, the newly created sub assembly not available in the model. Is there any idea to include this new sub assembly in the read only model without closing and reopening which requires more time.