Shopp breaks UM 2.0

With UM 2.0 installed, using TwentyFifteen and only UM 2.0 and Shopp 1.3.13 activated, I get the error below on the home page. No problem if Shopp is deactivated. UM 2.0 install info below.
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Fatal error: Uncaught Error: Class ‘um\core\Members’ not found in /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php:926 Stack trace: #0 /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php(301): UM->members() #1 /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php(187): UM->includes() #2 /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php(74): UM->__construct() #3 /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php(1068): UM::instance() #4 /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php(1072): UM() #5 /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/ultimate-member.php(26): require_once(‘/home/userdir/…’) #6 /home/userdir/mywebsite.com/wp-settings.php(305): include_once(‘/home/userdir/…’) #7 /home/userdir/mywebsite.com/wp in /home/userdir/mywebsite.com/wp-content/plugins/ultimate-member/includes/class-init.php on line 926
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### Begin Install Info ###

## Please include this information when posting support requests ##

— Site Info —

Site URL: http://mywebsite.com
Home URL: http://mywebsite.com
Multisite: No

— Hosting Provider —

Host: DBH: mysql.mywebsite.com, SRV: mywebsite.com

— User Browser —

Platform: Windows
Browser Name: Chrome
Browser Version: 62.0.3202.94
User Agent String: Mozilla/5.0 (Windows NT 10.0; Wi
n64; x64) AppleWebKit/537.36 (KH
TML, like Gecko) Chrome/62.0.320
2.94 Safari/537.36

—- Current User Details —

Role: um_non-member-admin

— WordPress Configurations —

Version: 4.9
Language: en_US
Permalink Structure: /%postname%/
Active Theme: Twenty Fifteen 1.9
Page On Front: Home (#2)
Page For Posts: Experts Blog (#2618)
ABSPATH: /home/userdir/mywebsite.com/
All Posts/Pages: 143
WP Remote Post: wp_remote_post() works
WP_DEBUG: Disabled
WP Table Prefix: Length: 10, Status: Acceptable
Memory Limit: 40MB

— UM Configurations —

Version: 2.0
Upgraded From: None
Current URL Method: SERVER_NAME
Cache User Profile: Yes
Generate Slugs on Directories: Yes
Rewrite Rules: Yes
Force UTF-8 Encoding: No
Time Check Security: Yes
JS/CSS Compression: No
Nav Menu Settings: Yes
Port Forwarding in URL: No
Exclude CSS/JS on Home: No

— UM Pages Configuration —

User: http://mywebsite.com/user/
Account: http://mywebsite.com/account/
Members: http://mywebsite.com/find-a-speaker/
Register: http://mywebsite.com/register/
Login: http://mywebsite.com/login/
Logout: http://mywebsite.com/logout/
Password Reset: http://mywebsite.com/password-reset/

— UM Users Configuration —

Default New User Role: member
Profile Permalink Base: user_login
User Display Name: full_name
Force Name to Uppercase: Yes
Redirect author to profile: Yes
Enable Members Directory: Yes
Use Gravatars: Yes
Gravatar builtin image: retro
UM Avatar as blank Gravatar: No
Require a strong password: Off
Editable primary email field in profile view: On

— UM Access Configuration —

Panic Key: B4uNZ0LcRH
Global Site Access: Site accessible to Everyone
Backend Login Screen for Guests: Yes
Backend Register Screen for Guests: Yes
Access Control widget for Admins only: Yes
Enable the Reset Password Limit: Yes
Reset Password Limit: 3Disable Reset Password Limit for Admins: No
Blacklist Words: 5

— UM Email Configurations —

Mail appears from: Somebody
Mail appears from address: somebody@somewhere.com
Use HTML for E-mails: No
Account Welcome Email: No
Account Activation Email: No
Pending Review Email: No
Account Approved Email: No
Account Rejected Email: No
Account Deactivated Email: No
Account Deleted Email: No
Password Reset Email: No
Password Changed Email: No

— UM Total Users —

All Users(88)
administrator(7)
subscriber(1)
um_non-member-admin(2)
um_member(1)
um_admin(3)
um_speaker(80)
none(0)

— UM Roles —

Administrator (administrator)
Author (author)
Contributor (contributor)
Customer Service Rep (shopp-csr)
Editor (editor)
Event Contributor (ai1ec_event_assistant)
Merchant (shopp-merchant)
Subscriber (subscriber)
Non-member admin (um_non-member-admin)
Member (um_member)
Admin (um_admin)
Speaker (um_speaker)

— UM Custom Templates —

N/A

— UM Email HTML Templates —

N/A

— Web Server Configurations —

PHP Version: 7.1.10
MySQL Version: 5.6.34
Web Server Info: Apache

— PHP Configurations —

PHP Memory Limit: 256M
PHP Upload Max Size: 64M
PHP Post Max Size: 65M
PHP Upload Max Filesize: 64M
PHP Time Limit: 30
PHP Max Input Vars: 1000
PHP Arg Separator: &
PHP Allow URL File Open: Yes

— Web Server Extensions/Modules —

DISPLAY ERRORS: On (1)
FSOCKOPEN: Your server supports fsockopen.
cURL: Your server supports cURL.
SOAP Client: Your server has the SOAP Client enabled.
SUHOSIN: Your server does not have SUHOSIN installed.
GD Library: PHP GD library is installed on your web server.
Mail: PHP mail function exist on your web server.

— Session Configurations —

Session: Enabled
Session Name: PHPSESSID
Cookie Path: /
Save Path: /tmp
Use Cookies: On
Use Only Cookies: On

— WordPress Active Plugins —

Shopp: 1.3.13
Ultimate Member: 2.0

### End Install Info ###