Hi NickZeik,
If you want to accomplish this, you can do so by making the grid editable. Go to the Grid Wizard for the grid you want to edit by clicking Edit on the top right of the grid object when customizing the screen. Go to Step 5 of 9 in the grid wizard that pops up and select the radio button to the left of Editing takes place directly in the grid. You can leave the rest of the settings here the same.
Unfortunately this will require a bit of extra work if you want the grid to remain read-only, as you will have to make each field read-only individually. You can do this from Step 2 of 9 of the grid wizard. Click on Advanced for each of the field names in the columns list, then check the box beside Make Read Only and hit Save & Close.
Hit Finish on the Grid Wizard and publish the changes to your screen, it should have the effect you're looking for. If it doesn't, just let me know and I'll see how I can help.
Hope this helps.
- Justin