Images can be uploaded to Reconstruct through the Data Manager. First you need to access the Data Manager for your project. Once you are in the Data Manager, you should click on the "Images" tab on the left-hand side of the screen. Once you are in the images tab, you can click on the "Upload Images" button on the top right-hand side of the screen, select the images from your local hard drive, and click "Open".
If the images you are trying to upload already exist in the project, a message will show in the Upload Activity window to explain. You can click on that message to see a list of duplicated images.
You can also drag and drop your images to the center of the screen.
Either way, you upload will start, and you will be able to see it's progress by clicking on the "Upload Activity" icon on the top of the screen.
While the upload is in progress, you can add more images using either of the two methods above. In this case, you will see more uploads showing in the upload activity box.