Click 'Texture' from the Menu Bar inside MODO 701. From the drop-down box, choose 'Substance' > 'Open A Substance'. Then choose "Bitmap2Material.sbsar".
This will place a Substance Item in the Item List. To edit the Substance properties, click in the Properties Tab. The Substance Properties button will be highlighted and the Substance properties will be available for editing.
In order to load Image Inputs into B2M, you will first need to load the bitmap tweak images into the Clip Browser. This is done under the Image Tab. Choose 'Load Image' from the pop-up box and load the images you would like to use as bitmap tweaks in B2M.
From the B2M Substance Properties side tab under the Image Input section, click 'Bitmap_Diffuse' from the drop-down box. The image(s) you loaded into the clip browser will now be available for you to select. Choose the diffuse texture image you want to use with B2M.