What are the key differences between v1 and v2 of DesignSpark Electrical?

Most of the free feature set and the UI were preserved. However, certain design limitations were imposed by the developer in version 2.0 which can only be removed by buying the SOLIDWORKS Electrical upgrade: https://designspark.zendesk.com/hc/en-us/articles/211239809-Is-there-a-paid-upgrade-for-DesignSpark-Electrical-and-how-do-I-unlock-its-limitations-

These new limitations in v2 include:
• 3 Electrical schematic sheets per project, including wiring line diagrams.
Limit of 3 pages does not apply to reports, cover pages or, appendix documents. The overall document limit per project remains 15.
• Reporting- Variants of Bill of Materials and Wire list by styles templates only. Two report configurations saved at any one time. No custom report templates.
• No 2D Cabinet panel drawing creation
• No Circuit macros manager
• No Terminal strip manager

If you previously used DSE v1 and are importing projects of >3 schematics into v2, here's what to expect with the new limit:

• Can OPEN a Project with > 3 schematic sheets.
• Can PRINT or EXPORT those schematics (e.g. export as PDF…)
• Can VIEW all of the pages in the schematic
• Can COPY 1, 2 or 3 Schematic pages out of an older Project and paste into a new project
(as long as it does not exceed to page limit in destination project)
• Can re-run the Reports included in the older design (with > 3 schematic pages)
• Can archive, save as template or duplicate project.
• Can run processes like wire numbering, project translation.
• CAN NOT edit any of those schematics- it schematic page count is >3
(you can delete some pages to get it 3
• CAN NOT copy any portion of a schematic page (in DSE)

If your existing project in v1 has more than 3 schematic sheets (say, 9 sheets), to continue editing the work in v2 you can split the 9 sheets into 3 projects with 3 sheets each.

Example: Below is a screenshot of a sample project with 4 electrical schematics (1 greater than limit). You can open this project in DSE v2 and preview the drawings in the small window below the document browser.  It just doesn't allow you to double-click the schematic and work on it, once the limit is crossed.

Next, you need to create a blank project using 'File -> projects manager -> New'.  Select the preferred standard and the new project should be listed in the document browser. You can delete the two blank schematics that are part of the new project so you claim back the 3 schematic limit.
 
Now, press down CTRL key and click on the schematics you want to move to this blank project. Right-click on the selection and press copy.  Go to the blank project, right-click on 'Document book' and Paste. 
 
Once you have checked the pasted drawings, you can delete them from the other project and free up its limit.

You can also change the drawing format of your title block to a larger paper size like A0, A1, B2, etc. to fit more content in one sheet.