WorkGuru supports the bulk creation of leads via a csv import template.  The import template can be uploaded on the imports dashboard (Administration -> Imports)

Select the leads option:

Lead Import Field Definition

ClientLead client name (must exist)Required
LeadNumberLead numberRequired
NameLead nameRequired
DescriptionLead description
CategoryLead category. Must match an existing category name exactly.Required
StageLead stage. Must match an existing category stage name exactly.Required
StatusLead status, (Options: Current, Won, Lost)Required
BudgetForecast quote valueRequired
Date of expected lead won date. DD/MM/YYYY

Lead closure probability as percentage (Number 100 = 100%)

OwnerQuote owner - must match existing user's full name exactly.Required

If you have lead custom fields, these can also be populated on import by adding a column to the import data with the custom field name (not label).  Note: Custom field name is case sensitive, has to match exactly.