There are several things you can create in Feng Office, elements of use in office and project management, and interconnected to your requirements.
You get a personal workspace with your user id. You can create a lot of things in the workspace as listed below. You can create other workspaces and give people permission to access the workspaces. Workspaces can have a parent workspace, letting you define a structure.
The structure might have a project as the parent then parts of the project as children. The parent might be a customer then the children might be projects and the grandchildren might be phases of projects. You could start with a workspace for each industry you work in or geographic areas then have customers as the children then projects as the grandchildren.
The use of workspaces is flexible and you can use tags for similar classification. If a customer is spread over several locations, you might leave location out of the workspace structure then add location as a tag.
Create a note. A note has a title and some text. You can select a workspace for a note and it defaults to your personal workspace. You can add tags. The options setting lets you switch comments on and off for regular users and for anonymous users. Custom properties lets you add extra fields with a name and a value.
You can display a list of people subscribing to your note. The default is yourself. You can switch subscribers on and off.
You can link objects to your note. The object can be anything in Feng Office except workspaces. You can link mail, contacts, documents, and a few other useful things.
Add a contact. Contacts have a first name, a last name, and an email address. You can optionally select a company and add all the usual stuff, department, address, and contact information. You also get the same custom properties, subscribers, and object linking as in Note.
A company entry looks like a contact entry with the addition of a timezone. Timezone would be a good addition for contacts because it is common for contacts within a company having different time zones. Australia has three time zones. America has four time zones.
The document option dumps you into a CKEditor page. When you select the Save button you can enter a file name and a comment. This is the next step up from a note but does not have all the options.
I presume you can create a document file then attach the document file to a note or task to define the use of the document.
Event has a lot of the common attributes including custom properties, subscribers, and object links. An event has a Subject instead of a Title and a Description instead of Text. You specify Date, Time, and Duration plus you can define repeats.
You can set reminders for events with a popup screen as the default. There is no SMS option.
You can invite people to an event and sent them email notifications. Invited people can be switched on and off similar to subscribers.
A milestone looks like an event with only a date, not a time, and no repeat or invite options.
You create a presentation the same as a document. The editing buttons look different.
Similar to an event. Tasks can have a start date and an end date. You can add a task to a milestone and to a parent task. You can estimate hours. You can allocate a priority. You can assign the task to a company or a person. Tasks can repeat and have reminders, something essential for repeating tasks.
Allocating tasks to a parent lets you schedule regular maintenance by creating a repeating parent task with a reminder then adding the individual tasks under the parent.
You can upload a file or create a link to something on the Web. They presumably become objects you can link to.
Something that could be confusing is the ability to link to objects from your file upload or Web link. There is the potential to link around in a loop that people will follow several times before realising they are not getting to the master note or task or document. Hopefully there are reports for links that create a loop and to highlight objects that are not linked to anything.
A Weblink is a URL with a Title, Description, tags, and subscribers. Weblink is also mentioned under Upload file.