Upgrading for Quicken MAC 2007 to Quicken Mac 2018 Problem

Not sure what issues you ran into to convert from QM2007 to QM2018 but I suggest that you make sure that Quicken 2018 for Mac will meet your needs, since it is not an upgrade from QM2007 but rather from Quicken Essentials (which was re-written from the ground up, starting in 2010), so there are some features that are still not there e.g. full loan amortization*, 2-line display, QuickMath, or are not as fully developed yet, e.g. Customized Reports, performance reports and stats (therefore some data may not carry over). You can start here:
https://www.quicken.com/mac/upgrader-compare

*NOTE: Support for fixed rate loans has been released as of  QM2017 v4.5.x but there is no announced timing for support for variable rate or simple daily interest loans.

Currently, the main advantages of QM2018 over QM2007 include the ability to sync cash, bank, and credit card accounts using Quicken Mobile for mobile devices (iOS and Android) and the ability to save receipts with transactions via computer or mobile device. There are a few other minor features that QM2007 does not have. Note that it has been announced that security fixes have ceased for QM2007 since QM2017 is released...see http://www.quicken.com/support/update-quicken-mac-2007-support-policies-may-2016 yet online access will continue as long as the FI/Bank supports it and their security updates don't prevent it.

Please note that QM2018 is now a subscription-based product currently available for 1 year directly from Quicken or 2 yrs from retailers (which are often cheaper than Quicken). (If you are able to find QM2017 which is a pre-subscription product, it is supported until April 2020).

You may want to review the List of Obstacles and Hindrances for Migrating from QM2007 or QWin to Quicken for Mac. 
Add your vote to any features that are missing for you. This will help make the transition easier for you when you are ready to upgrade by seeking to have the features you are used to in QM2007 end up in the latest version.

Your VOTES matter!

Be aware of data that will and will not carry forward: 
https://www.quicken.com/support/what-data-gets-carried-over
Then look at the updates since the original release here:
https://www.quicken.com/support/2018-release-quicken-mac-release-notes
You will also want to look at a more detailed comparison done by a SuperUser which also identifies nuances not mentioned elsewhere (and read on for comments from other users too on that same discussion thread): 
https://getsatisfaction.com/quickencommunity/topics/can-anyone-who-has-switched-from-2007-to-2015-he...
Take a look at the following videos to give you a better idea:
https://www.youtube.com/user/QuickenMac

Note that there are many differences that are rather subtle, that are not necessarily identifiable via documentation, for example, the 12-month budget feature does not allow including transfers, including investment income, selecting specific accounts, etc.

If you find that QM2018 does not meet your needs, the alternative is to obtain and run QM2007 Lion Compatible (LC), which will run on Mac OS X 10.6.8 to 10.13 High Sierra (so far*). 
NOTE: Since you purchased QM2018, users have reported being able to get QM2007 LC for free by contacting support. (Note not all reps know enough and you may get turned down at first, so try more than once). Please report back your results if you do try this.

* See Is Quicken for Mac 2007 (QM2007) Compatible with High Sierra (macOS 10.13)? 
(Early reports suggest QM2007 works on High Sierra but automatic backups do not seem to work, at least when using the new APFS drive format... but is ok with the HFS+ (Mac OS Extended) format on the boot drive only, NOT on external drives)

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