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

Select Choose file and Save to upload the lead activity template.

Lead Activities Import Field Definition

Column HeaderColumn Required on Template?Requires Value if Column Included?Notes
LeadNumberRequiredRequiredLead number.  Must match existing lead exactly
Owner
RequiredRequiredLead activity assignee. Matches to a user by username, email or full name
Type
RequiredRequiredLead activity type.  Must match an existing activity type name exactly
DueDate
Required
RequiredLead activity due date. Must be formatted according to the DateFormatShort language setting for your organisation. Default value: dd/MM/yyyy
CompletedDate
OptionalOptionalLead activity completed date. Must be formatted according to the DateTimeFormatLong language setting for your organisation. Default value: dd/MM/yyyy HH:mm
Description
OptionalOptionalLead activity description